# What's The Best Way To Post Efficiency On Ahb?



## PistolPatch (8/4/07)

*EDIT: AN ANSWER TO THE THREAD QUESTION (Based on the First Eighty Posts to this Thread)*

The poll shows clearly that currently there is no standard way in which people post their, 'AHB Efficiency.'*

I began this thread because my efficiency into boiler figure is always about 10% higher than my, 'final efficiency.'* I never put much thought into this until now as I when I do measure I am fanatical. I thought at the time of posting, that everyone's 'efficiency,' dropped during the boil. Theoretically though, this shouldn't happen. But, a few people are getting similiar figures to myself including one professional brewer. Other people are finding that their efficiency into boiler and final efficiency do match. Other people don't know as they only take one efficiency measurement per brew.

So, at this stage, the answer as to the best way to post your efficiency on AHB depends on your figures.

**Final Efficiency or AHB Efficiency*

One thing that the overwhelming majority of posters here agree on is that when measuring, 'Efficiency Into Fermenter,' losses to trub should be included in your calcs. So, in other words, if you end up with 23 litres in the fermenter and 2.6 litres in the kettle or in pipes etc, then you should regard your final volume as 25.6 litres. This figure does not have a name so let's call it our, 'Final Efficiency.' We could also call it our, 'AHB Efficiency.'

So...

*If Your Efficiency Into Boiler Figure Equals Your Final Efficiency Figure*

Obviously, if with your measurement regime, these two figures match, then you can post either figure as it will equal your 'AHB Efficiency.' Things are easy for you guys!

*If Your Efficiency Into Boiler Figure is Higher than Your Final Efficiency Figure*

Those of us who are finding their Efficiency Into Boiler figure is considerably higher than their Final Efficiency figure should, when posting publicly, use their final efficiency figure. If we do this then everyone's figures will be in agreement.

*Why Isn't Everyone Getting the Same Figures?*

At this stage we don't know. We have only a few figures to work from so far and so are currently trying to get more brewer's figures. If you are interested in this question or in contributing your efficiency figures then you should read this thread from Post #59  onwards. Post #59 contains a very pedantic template of how to measure your efficiencies written by you know who  Unless you're adding something like 250g of hops, then you can forget the hop adjustments contained in that post. The figures you come up with will certainly be close enough.

Please also vote in the new poll we have going here

*END OF EDIT. The original post is as follows...*

First poll I have ever done so God knows if I have done it correctly. Would have liked to add two more questions though, *'To mash, do you BIAB, batch or fly-sparge?'* and, *'Do you use BeerSmith or Promash,'* to derive your figures?

Look, you all know I read a lot but, still, after all my reading I can't see anyone defining what, 'actual' efficiency figure they post.

Wouldn't it be a good idea if we established some *standard 'AHB' measure of Efficiency?* And, if there is one, wouldn't it be a good idea if, someone like myself who does read a lot, actually knew about it - lol!

Personally I think improving efficiency (unless you are way out of the ballpark) is a silly goal. Adding a half kilo of grain to the bill to hit your target is probably a more sensible way of achieving an efficiency to match a recipe. Plenty of more important brewing stuff to focus on for sure.

But, when a recipe says 75% efficiency, it's nice to know what that actually means. What does it mean? I certainly have no idea. Are they talking about Brewhouse Efficiency and if so, then how is that relevant to the person who doesn't have the same lauter tun or trub losses as the recipe formulator?

I'm probably missing something really obvious here but, certainly when trying to compare ways of mashing I'm not. (Thanks AndrewQLD for that totally informative post of about 6 months ago )

Anyway, I'm going to whack in a post below of what I brewed today and all the relevant measurements. I'll try and write it in *a form that other people can easily copy and just change the figures.* I'd certainly love it if a few people could do this as the detail will certainly educate us bewildered brewers :huh: 

I'm hoping that this is either a really interesting topic to all or that I have missed something very basic. Either way, I'd be wrapped to be well-informed.

Happy Easter to you,
Pat


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## PistolPatch (8/4/07)

*Efficiency Figures for NRB's All Amarillo Ale*

*Grain Bill*
4250g Pale Malt (I assume Joe White Traditional Ale but don't know for sure)
0850g Munich 1 (I assume Weyermann but have no idea about grains)
0500g Caraamber (I asume Weyermann)

*This beer was* BIABed, batched , fly-sparged

*then boiled in* a Robinox 70lt Kettle (45cm high x 45cm diameter)

*The following figures* have been inputted to or derived from Beersmith ProMash 

Mash plus Sparge Water = 37lts
Mash Tun Volume = 70lts
Mash Tun Weight = 7.0kg
Lauter Tun Deadspace = Zero
Top Up Water for Kettle = Zero
Boil Time = 60min
Evaporation Rate = 28.3%
Loss to Boil Trub and Chiller = 2.60lts
Final Volume (Actual) = 23lts
Final Volume Into Fermenter = 23lts

*Efficiency Into Boiler* = 83.6% (33.49lts at 1.044)
*Efficiency Into Fermenter* = 67.8% ([email protected] 1.052)
*Actual Efficiency with Above Settings* = 67.8%

A few of the above figures are irrelevant to efficiency but I thought it safest and most informative to post them all. Why not!

Oh! And one final thing, that 23 litres above is of clear wort. So, finally, how do we distinguish between that and someone who will suck a kettle dry? (Ah! Just thought... Maybe by them posting the diameter of their kettle etc!)

Spot ya,
Pat


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## Stuster (8/4/07)

PistolPatch said:


> Are they talking about Actual Efficiency and if so, then how is that relevant to the person who doesn't have the same lauter tun or trub losses as the recipe formulator?






PistolPatch said:


> *Efficiency Into Boiler* = 87.9% (35.25lts at 1.044)
> *Efficiency Into Fermenter* = 67.8% ([email protected] 1.052)
> *Actual Efficiency with Above Settings* = 67.8%
> 
> Oh! And one final thing, that 23 litres above is of clear wort. So, finally, how do we distinguish between that and someone who will suck a kettle dry? (Ah! Just thought... Maybe by them posting the diameter of their kettle etc!)



As you are suggesting, this is why it's best to quote your efficiency into boiler (also called mash efficiency). I think the efficiency into the fermenter is only relevant to your system and is no very useful to anybody else using a recipe of yours. If I want to use the recipe above on my system and you post your efficiency into the fermenter, I'd need to know how much you lose in your kettle as well. It would be good if we can all use that figure as you say and standardise things.

AFAIK, efficiency in Promash is efficiency into the boiler. Another reason to stick to that figure.


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## bayWeiss (8/4/07)

I think most efficiency numbers are pre-boil (i.e extraction of sugars from mash). This is really all anybody would care about because all of the other gravities can be calculated from boil-off, etc. For example, Beertools uses only preboil efficiency.

I do not really agree that increasing efficiency is not important. It is true, that we are homebrewers, but I think it is important to know how/why the efficiency numbers go up (increasing) and down (decreasing). Ultimately this allows for repeatability, which is key.

For example, I was positive I had my efficiency pegged, and all of the grains that I used were milled on the same device. But, somehow the efficiency on my last batch dropped 10%, which threw my OG off significantly. It basically changed my beerstyle from weizenbock, to some kind of dunkelweizen/halfbock. :lol: 

cheers!


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## Ross (8/4/07)

Hi pat,

For starters - Set your "loss to boil trub & chiller" to zero & just up your final volume to compensate.
This has been discused many time before. Beersmith & i believe Promash both have the same problem if you fill in a loss figure - It throws out your efficiency & your bittering. Leaving wort behind in your kettle, should make no difference to the bitterness of the wort, but if you play around with that loss figure, you'll see it change dramatically. ALWAYS SET TO ZERO.

cheers Ross


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## browndog (8/4/07)

What Ross said Pat.... Also, I note you are only loosing 1.75L to the mash, is that one of the features of BIAB? the normal figure is about 1L/kg of grain.

cheers

Browndog


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## NRB (8/4/07)

Ross said:


> Hi pat,
> 
> For starters - Set your "loss to boil trub & chiller" to zero & just up your final volume to compensate.
> This has been discused many time before. Beersmith & i believe Promash both have the same problem if you fill in a loss figure - It throws out your efficiency & your bittering. Leaving wort behind in your kettle, should make no difference to the bitterness of the wort, but if you play around with that loss figure, you'll see it change dramatically. ALWAYS SET TO ZERO.



Interesting, I never knew that. I've just played around with my water needed calculator, is that where I change it all? I've attached a screen grab of my new settings... let me know.

I always took brewhouse efficiency to mean how much sugar I extracted from the grain that made it to fermenter; into the boil would be a better standardised figure to go by.


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## domonsura (8/4/07)

Again, what Ross said, set all the loss to zero. I was very confused by the whole efficiency thing for quite a while, as I didn't seem to be able to achieve a consistent efficiency, and it seemed to me that all the little bits in Promash opened the way for far to many 'estimates' of what losses were. So I ended up just ignoring all that and setting it to zero (which these days is accurate for my mashtun anyway with the outlet in the floor)
I would think that the best place to peg efficiency is into the boiler, because that's the first stage after what you are trying to measure - which is how much sugar you have managed to wash out of the grain after all. (IMHO anyway, I'm no expert...)
Now I just try and iron things out by gradually trying to get everything else consistent which is why I scored a new mill which will get my crush consistent instead of the all over the place crush I was getting with my marga.
Overall, I my opinion is that unless you can nail your grain weights, your crush, water composition and your mash temp/sparge process etc down to exactly the same every time, (while it is important to achieve enough efficiency to get the beer you wanted), the _exact[/] consistency % is a fairly arbitrary figure anyway in the sense that it is subject to so many variables. Having said that though, the refining of the techniques that this site and all the communication induces and the technology that is now available to us for our processes, we should be able to achieve pretty consistent results.....have I managed to stretch myself to both sides of the fence?  Not sure,....

The water needed one still throws me out sometimes, but I'm still playing with/learning about that one._


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## PistolPatch (8/4/07)

Thanks for all the info so far guys. Only a small part of the above has been discussed before (such as software settings) that I am aware of. I am certainly not aware of an accepted efficiency figure to post on AHB and the poll results reflect this uncertainty. Agreeing on a figure should be of value.

On my way out Browndog but I have last nights mash remains in a plastic bag and I'll weigh it later to see exactly what the mash loss is as a matter of interest.

One other thing...

Is everyone reducing their volume into boiler by 5% to allow for wort expansion?

Spot ya,
Pat


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## Trent (8/4/07)

Pat
I usually just base my efficiency on what I have in the kettle postboil. I have 2.5L deadspace in the bottom of my kettle, so if I get 23L into my fermenter, I base my efficiency on 25.5L at whatever my postboil gravity happens to be. I only lose about 4L an hour during the boil, and it seems that I only lose about 800mL water per kilo of grain (I am one of them people that measures every mL that goes in, so I know what I am gonna get out!). I dont use any computer programs, I just do all my workings out on paper.

BayWiess
I, too, fairly well have my system pegged, I base the majority of my recipes at 75% efficiency, but notice that when I am making a bigger beer (which I am pretty sure a weizenbock is) I need to calculate my grain on a 65% efficiency and usually hit my target bang on. If I am heading north of 1.100 I will probably calculate on a 60% efficiency. It almost ALWAYS drops in efficiency when you are doing a big beer. Not sure if it is due to less water per kilo of grain used to rinse, or the higher gravity makes it thicker, and hence less easy to rinse the sugars, or some other strange chemical reaction. I would say that next time you plan on doing a beer over 1070 or so, drop your efficiency calculations by 5-10%, and you will find you will be alot closer to your intended target than if you just assume you will always get the same efficiency no matter what. BTW, my efficiency goes up into the mid-high 80's when I do a double batch of beer, which could be due to double the amount of water (and grain) for the same amount of mashtun deadspace. IMO, efficiency isnt always a fixed thing, depending on the kind of beer you are brewing, but should be relatively constant if you are brewing the same (or similar) beer alot.
All the best
Trent


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## lucas (8/4/07)

are pre-boil and post-boil efficiencies actually different? I thought efficiency was the measure of sugars extracted compared to total possible sugars from the grain, which would be the same both before and after the boil. evaporation would have no effect on that extraction figure, only the concentration of the wort.

on the topic of whether we should bother trying to improve our efficiency, I'd say no as long as you can consistently get the same %.


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## Stuster (8/4/07)

lucas said:


> are pre-boil and post-boil efficiencies actually different? I thought efficiency was the measure of sugars extracted compared to total possible sugars from the grain, which would be the same both before and after the boil. evaporation would have no effect on that extraction figure, only the concentration of the wort.
> 
> on the topic of whether we should bother trying to improve our efficiency, I'd say no as long as you can consistently get the same %.



Agreed. There is no way that the efficiency can change pre- to post-boil (other than measurement error).

Increasing efficiency can be a good thing. If you are getting only 50%, there may be something about your temperature control or water chemistry that is not giving you good conversion or perhaps you have too much dead space in your mash tun. And while it's not the most important thing to focus on, saving a few dollars by getting your system set up well is not a bad thing, is it?


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## PistolPatch (8/4/07)

On the improving efficiency bit I should have said that I meant if you are within 5% or so of the norm, I don't think it's worth a beginner worrying about it a hell of a lot.

Also, I have edited Post #2 as I forgot to allow for wort shrinkage last night. So Efficiency into Boiler is 83.6%.

*Now I'm Totally Confused!*

I would have thought, like you guys that pre and post-boil efficiency would be identical but it's not coming up that way.

If I change my Volume Into Fermenter to 25.6 lts (23 lts + 2.6lts loss to trub and chiller), my Efficiency Into Fermenter shows as 75.5% whereas it should match the 83.6% above. Why doesn't it????

I'm not even going to go into what the Actual Efficiency Based on Target Volume figure does.

Grrrrrrr.

It is also making no difference to my 'Efficiency Into Fermenter' figure when I change 'Losses to Trub and Chiller to Zero' so this must only affect the sparge water calculations. Right?

*So, What's the Best Answer to the Thread Title?*

I sort of thought this question had been answered above but now I'm not confident.

Besides the new questions I have just asked, if you look at this poll, half do it one way and the other half do it another  This shows that further discussion resulting in a brief and clear description of how to post your efficiency on AHB should be of real value to many.

I'm going to lunch while you guys come up with this definitive answer. Hurry up!


Pat


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## razz (8/4/07)

I'm not trying to be a smart arse Pat, but couldn't those who are interested simply mash a given volume of grain, sparged and cooled to give a "benchmark" for their systems/mills ? :blink:


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## Stuster (8/4/07)

How are you measuring the volume into the kettle? Are you correcting for temperature? (I am very impressed that you can measure the pre-boil volume down to 2 decimal places. :lol: ) How do you measure your losses to trub so exactly as well?


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## MHB (8/4/07)

Now I get it, I have often wondered (well, been incredulous) about some of the "reported" efficiency figures.

To my mind the only number that matters is cast wort (brewhouse) efficiency, not saying you dont need the other figures on the way.

But ultimately - how much wort you get is what counts.
For a home brewer a brewhouse efficiency of 70% is pretty good. Using the brewhouse yield you can work backward to tell you what you need to put in to get a given amount of wort.

MHB


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## oldbugman (8/4/07)

yeah, really all you care about it you a X amount(litres) of Y Gravity from Z grains.


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## PistolPatch (8/4/07)

Stuster said:


> How are you measuring the volume into the kettle? Are you correcting for temperature? (I am very impressed that you can measure the pre-boil volume down to 2 decimal places. :lol: ) How do you measure your losses to trub so exactly as well?



Ha! Of course the decimal places do not reflect the accuracy of measurement - they just multiply out that way. Here's what I do...

Measure depth of wort in centimetres at beginning of boil and divide this by 0.61 (as every 0.61cm = 1 litre). I then multiply this by 0.95 to allow for wort expansion. (I also momentarily turn the flame off to try and get a more accurate ruler reading.)

My losses to trub are measured by emptying whatever remains in the kettle into a 3 litre brewing jug. That's where the 2.6 lts comes from. (The 2.6lts does not include the hop debris removed with the hop sock.)

Thanks for all your answers above too mate 

Razz: Not sure if your idea is good or not. I'm confused enough as it is - lol

MHB: Glad to see I'm not the only one!

Bugwan: The reason for trying to find a standard here is so that when people post a recipe, it can be translated correctly to your own system. If you make your own recipes up then it doesn't really matter which efficiency figure you prefer. In this case, it's just as MHB says, what counts is how much wort you get in the end and at what gravity.

Browndog: Just weighed the mash from last night on some bathroom scales and got 3 different readings varying from 5 to 7.1 kgs depending on how I placed it on the scales. But, in answer to your query, from this and past brews, it does seem that BIAB retains less water. I never realised until now that this is the reason why BIAB gives a higher efficiency than the batching I used to do. For example, if it retained another 3 litres, this would drop the efficiency into boiler by 10%. Thanks mate - a long-time question answered!


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## TidalPete (8/4/07)

PistolPatch said:


> Browndog: Just weighed the mash from last night on some bathroom scales and got 3 different readings varying from 5 to 7.1 kgs depending on how I placed it on the scales.



Pat, 

I have read this thread with much interest & recommend to you to ditch the bathroom scales for something more accurate.
Screwtop & myself got our hanging fish scales (To 50kg) on eBay for around $30. Do it mate as it will help you iron out your efficiency problems.

:beer:


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## poppa joe (8/4/07)

WOW.....
NOW i am confused///  
PJ


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## TidalPete (8/4/07)

poppa joe said:


> WOW.....
> NOW i am confused///
> PJ



OT I know but I love your logo mate. :super: 

:beer:


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## poppa joe (8/4/07)

Thanks Tidal Pete..
Beside working out "this efficiency bit " for my next BIAB(Never done efficiencybefore)  
But only done 1...
Have to try n figure it out.. Gotta watch this thread..Get some info :blink: 
Gotta work out how to do these Logo things(With apologies to Franko..The KING of Logos)  
PJ
B.O.A.B=Brewing On A Budget


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## PistolPatch (9/4/07)

Have just had another read through here and really only have one question left. I've gone through quite a few of my past figures and they all pretty similiar to what I put in Post #2 so...

*Why is my Efficiency Into Fermenter (incl. trub losses) about 10% lower than my Efficiency Into Boiler? Why aren't they the same?*

Obviously, I'm not reading my measurement ruler incorrectly by 2cm every time or mis-reading the hydrometer by 1 Brix each time either. This is my only remaining area of confusion.

(Hi Pete: All my grain is measured on professional scales. The bathroom scales I used yesterday were just to check a little sub-topic out that arose above. Thanks mate.)


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## Corny (9/4/07)

Efficiency in a recipe doesn't interest me. The gravity of the recipe is more important TMWOT. If the gravity is above or below recipe gravity at my systems efficiency setting then I adjust the fermentables keeping the percentages the same, ie: if a recipe calls for 45% wheat and 50% ale malt and 5% sucrose then adjust the amounts up or down keeping the percentages roughly the same until reaching the required OG.

FWIW: 4% cooling loss from pre boil to post boil temp of 25C.


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## bayWeiss (9/4/07)

PistolPatch said:


> *Why is my Efficiency Into Fermenter (incl. trub losses) about 10% lower than my Efficiency Into Boiler? Why aren't they the same?*



You are right, there is a problem.

If your pre-boil volume is 33.49L @ 1.044
and your post-boil volume is at 25.6 (23L + 2.6l), you should have an OG of 1.058 going into the fermenter instead of the 1.052 you reported.

There can only be a few things wrong.
1. You are not evenly mixing your wort before you measure (systemic error if you have the same routine).
2. Your hydrometer is off (systemic error)
3. You are leaving sugars behind in the cold break/trub (systemic error)
4. You are boiling over (not likely)
5. You are losing sugars to burning on the kettle (not likely, I think it would be obvious)

When I say "systemic", this means you could be doing the same thing in all of your batches, which would explain your consistency in error. (as opposed to random error)

I have just read that sugar water is twice as dense as pure water, so it is quite likely you might be leaving much of the sugar behind in the trub (if you let it sit a while, and drain from the kettle in a certain way). This has never happened to me, but I typically do not have so much cold break at all lately. 

Come to think about it, 2.6L/ 25.6L is about 10% of your final liquid volume. If we make the assumption that the denser sugar water sinks to the bottom, I think it is entirely feasable that you would lose .006 points of your gravity.

just some thoughts/ideas...
cheers!


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## PistolPatch (9/4/07)

I've just done another brew and in light of Bay's detailed post above have taken some detailed measurements that you may find interesting. *Efficency does a consistent decline during the boil.*

I took readings at the intervals below. This beer is a low alcohol beer (60% of the grain bill of the beer in Post#2) hence the low readings. All efficiencies were calculated using the Efficiency Into Boiler section of Beersmith.

*Start of Boil:* 32.1lts at 1.0295 = 92.6% Efficiency Into Boiler
*Middle of Boil* 28.8lts @1.032 = 88.7% Efficiency
*End of Boil* 25.9lts @ 1.0340 = 84.5% Efficiency

This confirms all my previous data. Once this is chilled I'll also post the volume into fermenter etc.

Has anyone got any solid data available that agrees or disagrees with the above conclusion? Is anyone else out there scratching their head?

Cheers
Pat

Refractometer versus Hydrometer: Whilst it is totally irrelevant to the above exercise, my current hydrometer comes up 3 points lower than the refractometer. My old hydrometer which recently went to the big brewery in the sky used to match the refractometer exactly though.


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## oldbugman (9/4/07)

PistolPatch said:


> *Start of Boil:* 32.1lts at 1.0295 = 92.6% Efficiency Into Boiler
> *Middle of Boil* 28.8lts @1.0288 = 88.7% Efficiency




How'd you boil off water and go down in gravity?


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## PistolPatch (9/4/07)

Whoops! A typo mate. Have fixed it now. (1.032)

Have also got rid of an edit I threw in there about the refractometer reading climbing. I'd forgotten that the reading continues to climb over time even when cooled. Here we an hour later and it has climbed to 10 Brix!


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## PistolPatch (9/4/07)

The *final result confirms the efficiency drops during the boil.* 

Final Volume (23lts in fermenter + 2.65lts trub) = 25.65lts
Original Gravity = 1.0336 (Confirmed with hydrometer)
Efficiency 'into Fermenter' = 82.9 (Close enough but still lower than the 84.5 at end of boil.)

The above is about a 10% loss during the boil, confirms my prior brew figures and shows that there seems to be no relevant measurement errors.

Maybe some sugars evaporate off? Does anyone know for sure the reason as to why the efficiency drops? I'm hanging to know!

:blink: 
Pat

(Excuse the decimal points, just easier for me that way.)


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## Stuster (9/4/07)

Rather than your boil breaking the laws of physics, my guess is that your volume calculations are out. I'm rather wary of calculating the volume from the height. You could actually measure the volume empirically. You could also mark off the volumes on your ruler/a stick and save yourself the trouble of working it out every time. Just a possible area for error.


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## bayWeiss (9/4/07)

PistolPatch said:


> The *final result confirms the efficiency drops during the boil.*
> 
> Final Volume (23lts in fermenter + 2.65lts trub) = 25.65lts
> Original Gravity = 1.0336 (Confirmed with hydrometer)
> Efficiency 'into Fermenter' = 82.9 (Close enough but still lower than the 84.5 at end of boil.)



I have never used refractometers... but, are they accurate to .0001 (four places) gravity points?


Also, at these low gravity readings, i believe an error of .001 (1, at three places) will throw your percentage points off by 3-4%.

At the end of the day, it does not seem like a big deal, and your last low gravity batch numbers seem pretty reasonable. Your first batch, was WAY off though.

If you want more info on how to calibrate (two point cal), and make volume measurements, follow this link Calibrate your Hydro.

cheers!

BTW, I am super impressed that you got 93% efficiency with BIAB!


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## NRB (9/4/07)

I'm sorry Pat, but I don't believe your numbers. Something's wrong with either your refractometer or volume measurements. It's technically impossible for it to occur.


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## PistolPatch (9/4/07)

I can't see how my figures are incorrect as they were measured in two different ways. Both refractometer and hydrometer were used for gravity - cooled to 20 degrees. Volume was measured both with ruler and by measured jug and/or fermenter. Wort shrinkage was allowed for (5% instead of 4% but this makes no significant difference.)

Bearing this in mind, I'm very confident in the measurements.

I'd be wrapped if someone else had some measurements though or could take some on their next brew as I am aware that mine do contradict what we think to be true.

I certainly can't find any pre, during or post boil measurements anywhere I've looked in books or the net unfortunately. Has anyone got some or is brewing in the next few days and can get us some?

bayweiss: The BIAB does get a higher efficiency than normal. That into boiler figure is high but I have had it before several times in the few figures I do have recorded. (The figure in the next paragraph you will be more familiar with though.) It wasn't until yesterday, thanks to Browndog, that I realised that this is mainly due to not as much water being held by the mash and, of course, there is zero 'mash tun' deadspace. Those extra 3 or so litres make a big difference....

Same thing happens at the other end of the brew. For example, if we ignore the trub loss above of 2.65lts and only consider the 23 litres in the fermenter (the Brewhouse Efficiency) of this brew then the efficiency drops another 7.5% to 75.5%!

This is just one of the many reasons* why I started the poll, the results of which show that currently people are using a variety of ways to report their efficiency and that's why we see such a wide range of efficiency figures reported. There certainly seems to be no universally accepted practice.

As for decimal points, they were not thrown in to reflect accuracy but more the way that the figures multiplied out. eg I posted 7.2 Brix as being equal to 1.0295 gravity rather than rounding it up to 1.030. I've left it to the reader to do the rounding. Obviously the same goes with volume measurements.

Thanks guys and I have my fingers crossed that a few other troops can throw some sets of figures in. I'm finding this interesting but also pretty frustrating!

Spot ya,
Pat

*One other reason is that on the occassional times when I do bother to seriously measure efficiency all the way through I get bewildered by my own findings even though I am very thorough at these times. I end up dismissing my own figures and second-guessing myself. e.g. I'll say, 'That's too high,' and then say, I must have forgotten to allow for wort expansion. The general theme of my figures though is always the same hence my huge desire to see some other people's raw data.


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## PistolPatch (10/4/07)

Noticed there have been several reads while I was editing the above post.

If you want a quick summary of that last post including the edits, then just read the last paragraph of it 

I know that a few other guys are following this so anyone that is willing to provide or gather some data will end up helping a lot of people out. I'm sure that the scientists will agree that analysing one person's data (mine) any further will be nowhere near as useful as having some new raw data.

Thanks,
Pat


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## PistolPatch (10/4/07)

This post is going to be interesting. Been writing for 5 or more hours now. I might do one final read before posting.

[Started this post when I got home so it's a 'live' post. I am now drinking Batz's Altbier (the best!) so read at your own peril - you know the drill  Not a bad post so far though. Whoops! Could be a contender for some morning edits but am not sure as yet!]

Well I've just got home, all excited, and find that after nearly 100 reads, no one has put their hand up to offer or gather some more raw data. While this is lol - I'm very dissapointed.

I've even just double-checked my ruler calibration, which I knew was correct anyway, just to be totally sure that I'm not an absolute idiot (well, in one area anyway ) So, I'm now as sure as I can be, that all my measurements on that last brew were as correct as I can get them.

And, if it's that hard to get good figures well why bother? NRB's and Batz's recipes are working bloody well for me without bothering about efficiency measurements (see 3 below.) Just check the length of my posts while drinking their recipes. That's solid proof!

Obviously this thread is going to temporarily die for all or a combination of several reasons. Some that have crossed my mind since beginning this post are...

1.Some readers are sure that my figures are wrong. They know I'm missing something totally obvious and that I just can't see it. But they haven't posted/PM'ed/emailed me to explain what that is or the data they have that backs that up. They should do so.

2. Many people reading this thread are also having the same doubts as myself but don't feel comfortable in posting their doubts or their figures. Fair enough!

3. Other people have established a brewing routine and rely on one efficiency figure. It works for them (as it will) and they really have no interest in all this. Fair enough as well and a large part of me actually agrees with them. (Who cares as long as the beer tastes great?)

4. Well, the fourth reason that comes to mind has to do with cognitive dissonance which I've talked about once before so, if you're interested, do a search  It includes aspects of some of the other reasons here but with the most unproductive result.

I'm not talking here about the guys who have told me to check my figures - their posts actually, to me, show either quality thinking and/or motivation and they are the sort of buggers who will doubt themselves so I better send them a PM saying, 'It's not you!' or, better still, will send me a PM saying, 'Was it me?' (Come to think of it honestly, I'm not going to have time to send PM's in the next few days to the guys I'm thinking of. PM me if you are in doubt though!)

There is a big difference between being active and dismissive. Take NRB's post above saying, 'Sorry Pat. I don't believe your figures.' To me, this is an active post. It is not dismissive. He's just saying, 'Mate, you must have buggered something up. Can you take another look?' Haven't thought this through entirely yet but it may actually be the best post here for reasons I better not go into. (Read the. 'My Thinking,' thread. That thread is all about innocent courage which I think is a quality of the true scientist.)

5. The final reason I can think of and not necessarily the last, is that I have bored everyone to death with my long posts. Quite possible and once again, definitely fair enough. (I certainly get a lot of laughs on this - Jayse. the moderator, did a cracker the other day on the 'My Thinking' thread where two people went way OT. He basically said, "Just dropped in here and saw 5 PP posts in a row. There's no way I'm reading that! But, you two guys settle down.' Unfortunately his post got deleted in the impressive fracas! Donya Jayse - not that you would be reading this - lol)


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## PistolPatch (10/4/07)

[Had to split post - too many emoticons]

I'm very keen on my figures being proved wrong or right. Either way would certainly be great for me and many others (how many times have I said that in this thread?)

But there is a reluctance out there to do so and this is what has truly piqued my interest and prompted the above essay. Situations like this often yield fascinating results.

So, for those still interested in the original question of this thread (which a few people have tried to side-step) can you send me a PM or email saying, "Yep! On my next brew, I'm prepared to do some serious and honest measurements."

Obviously, NRB, Stuster and Bayweiss will be in on this :super: 

Well maybe not. Not everyone on AHB (probably no one!) has the time like I do to think on one thing for way too long so, you guys, if you have the time then great but if not, don't think I don't appreciate the time you have taken here already. I certainly do.

I reckon we need at least a dozen sets of figures to set this straight so if no one PM's me from here to offer their measurement services then I'll start asking the AHB'ers I know individually.

Please don't put me through that!!!

I've been up since 4:30, have been waiting for a phone call for 5.5 hours (so it's taken that long to write this!) and am starting to get in an impatient frame of mind.

What? Me?

LOL
Pat...

(That's a very long read sorry guys. Hopefully, it will end up giving us s though.) 

P.S. AHB has already proved accepted fact wrong once so why not again?

P.P.S. As a matter of interest the whole of the above post was written under the, 'Fast Reply,' button. Most of my long posts start out this way. This is proof that I do start out with good intentions. I think I need an AHB Personal Restrainer. Anyone got any sisters who need a job? (Full-time!)


--------------------

I'm not as think as you drunk I am.


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## brendanos (11/4/07)

Too long didn't read.


















...just kidding, but it was some pretty classic late night PP.

I love that you're determined to get to the bottom of the whole efficiency debacle, I'm just sorry that I have nothing really to contribute.

Are you after BIAB figures in particular, or just any-method efficiency figures? If it's the latter PM me about the sort of numbers you're after and I'll see if I can help contribute to your empirical data heap over the next few brews - all in the name of science!


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## PistolPatch (11/4/07)

Fair enough - lol!

Oh brendanos I didn't see the rest of your post til just now - too many spaces!

'Classic night PP' - you should see what else I have written or emailed, Fun and games tomorrow but I'll be working. No worries! 

Mate your post is a great end to a great night. Just the post I was looking for! I'm chasing any figures - batch, fly or BIAB.

Give me a day or two and I'll try and write a little more specifically what figures would help - only two off the top of my head???

OMG! Just saw you are just around the corner. We have to have a beer!

Can't wait!
Pat

Perfect!


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## bayWeiss (11/4/07)

PP,

May I suggest an idea. I would actually do this myself, but I am equipment-less (this means without a hydrometer) at the moment, and would not be able to for a few weeks or so. 

Since the whole question is about measurements starting at the moment before boiling, to the end of boil, the following steps should suffice in getting an idea of what is going on.

1. Dissolve 225grams of corn sugar (or whatever sugar) in 2.5L of water.
2. Take a gravity reading.
3. Boil the solution for 15 minutes or so... 
4. let it cool, measure volume and take another gravity reading.
5. Boil the solution for another 15 minutes, and repeat step 4.

Now, you will have three gravity readings, and three "cooled" volume readings.

I think this is as controlled a test as you can do.

The efficiencies for all three volume and gravity reading points should be identical. If they are not, then this would be one's "system" measurement error/tolerance.

Like I said, i would do this myself, but i do not have equipment at the moment (I am moving).

cheers!


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## Stuster (11/4/07)

brendanos said:


> Too long didn't read.
> ...just kidding, but it was some pretty classic late night PP.



:lol: 

Yep, I'm in. It does take time for these sort of things to happen though. I'll probably be mashing this week, but it's going to be a parti-gyle brew so that might not be quite as helpful. Still, I've recently got a refractometer so it'd better do something for its living. I might also do bayWeiss' experiment to calibrate my hydrometer and refractometer (probably do it using LME).


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## Trent (11/4/07)

Jeez, PP, you sure can type!
Anyway, I think that Baywiess is on the money with the experiment bit, but I am not exactly sure how you are going to tell if the efficiency has gone down, specially in 2.5L. Maybe you can PM him and work out exactly what sort of numbers you should be looking for to see if it is actually the boil that drives off some fo the sugars.
For the record now, I belive you Pat. MY PRE BOIL EFFICIENCY IS ALWAYS HIGHER THAN MY POSTBOIL EFFICIENCY! Just thought I would put it in capitals so anyone skipping through wouldnt miss it. I include the trub and kettle losses in my calculations, so there is nothing missing there, but I find I always have 5-10% more efficency into the kettle than I do coming out (and my pickup tube is on the bottom of the kettle). I just did an IPA that had 83% efficiency preboil (26L at 1058) and 76% postboil (approx 23L at 1060), 26 x 58 = 1508. 1508/23 = 65.5. 1065. Thats what my OG SHOULD have been, but it wasnt. It never is. Just part of the way my system seems to work. I measure my volumes empirically (calibrated metal rod), and check with refrac and hydro, cooling beforehand. So, maybe we are wierd, but I believe your numbers, Pat, cause obviously I am in the same boat. I just determine all my recipes to postboil targets.
All the best
Trent


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## Screwtop (11/4/07)

PP I didn't read all of your posts as I am going away next weekend and don't have the time. 

But as for the confusion re BREWHOUSE efficiency in Beersmith, I might be able to help. This bugged the shit out of me for a long time, till I gave up and only bothered using Mash Efficiency. Think a quick (read SHORT) email to Brad Smith would clear things up, but here's my take on the situation.

You enter the parameters for your equipment into Beersmith.

You enter a recipe and select/set the Style, then select the Equipment and Brewhouse Efficiency or maybe you leave these set to default.

Beersmith uses some of the figures from the Equipment selected to calculate post boil volume and gravity.

If the actual results vary from the predictions then the actual Brewhouse Efficiency figure will vary from what you had set. Because your system produced an incorrect result based upon the prediction, which was based upon the equipment data. If the actual post boil results match the predicted results then no negative or positive would be applied and the actual would be the same as the Brewhouse Efficiency set for the recipe. 

Think that when it comes it comes down to Brewhouse Efficiency it's firstly a matter of experimentation then applying known results to your equipment settings in Beersmith.

Does this make sense


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## lucas (11/4/07)

I'd join in the experimenting but I've only just calibrated my stick to measure volume and I'm not sure how much I trust it yet. up until now I've been using the "blind faith" method that my volumes are "about right", but that wasnt always working out so well.

how exactly are people calculating their efficiencies? how are you actually coming to your figures? I played about with this method from byo and PPs volumes and gravity and found what bayweiss was saying to be quite true. Changing SG figures by only a very small amount was changing the amount of sugars extracted by a significant amount. I've no explaination why you might consistantly get a positive limit-of-reading error before the boil and a lower one after though, perhaps some really sugar is disappearing somewhere? no idea...

I meant to check in DGB how daniels does efficiency, but I didnt get around to it yet... and i'm dreading the fact that it's probably been done in retarded imperial units that make no sense!


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## brendanos (11/4/07)

bayWeiss said:


> but I am equipment-less (this means without a hydrometer) at the moment



I had a dreamnightmare last night that I was in a foreign country (possibly an african desert), was going to brew the next day, and was given the news that someone had broken my hydrometer. Man was I angry.

(Sorry, OT)


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## Hogan (11/4/07)

PistolPatch said:


> I'd be wrapped if someone else had some measurements though or could take some on their next brew as I am aware that mine do contradict what we think to be true.
> 
> I certainly can't find any pre, during or post boil measurements anywhere I've looked in books or the net unfortunately. Has anyone got some or is brewing in the next few days and can get us some?




OK Pat - you've got me. Today I was thinking of just relaxing in the beautiful Southern Highlands autumn sunshine and cooking a brew. But I decided to give you a hand and jot down down a few stats that may (or may not) be helpful to your current efficiency issue. 

My recipe is a basic german pilsner which I have done a couple of times but today I am lowering the mash temp to get a dryer result. I use Beersmith and I have included a snap shot of my equipment and the finished efficiency details. My previous brews (once I got my system sorted out) have all come in around 82% so I have set my Brewhouse percentage at 80%.

BeerSmith Recipe 
Recipe: Schultz German Pilsner-3
Brewer: Hogan

Style: German Pilsner (Pils)
TYPE: All Grain
Taste: (40.0) 

Recipe Specifications
--------------------------
Batch Size: 25.00 L 
Boil Size: 31.76 L
Estimated OG: 1.048 SG
Estimated Color: 8.0 EBC
Estimated IBU: 27.4 IBU
Brewhouse Efficiency: 80.0 %
Boil Time: 90 Minutes

Ingredients:
------------
Amount Item Type % or IBU 
4.00 kg Pale Malt (Barrett Burston) (3.9 EBC) Grain 83.9 % 
0.50 kg Munich, Light (Joe White) (17.7 EBC) Grain 10.5 % 
0.27 kg Cara-Pils/Dextrine (3.9 EBC) Grain 5.7 % 
53.00 gm Hallertauer Hersbrucker [3.30%] (60 min) Hops 16.6 IBU 
40.00 gm Tettnang [4.70%] (20 min) Hops 10.8 IBU 
1 items Whirlfloc Tablet (Boil 15.0 min) Misc 
2 Pkgs Fermentis (DCL Yeast #34/70) Yeast-Lager 


Mash Schedule: Micks Infusion Mash
Total Grain Weight: 4.77 kg 
----------------------------
Name Description Step Temp Step Time 
Step Add 14.31 L of water at 71.6 C 63.0 C 90 min 


All gravity measurements were done on the refractometer using Docs conversion chart. My mash tun is a rectangular esky and I use a five bar cross cut slot manifold. 





Gravity stats are as follows:

Strike temp was right on the money and stayed between 63-64c for the whole of the 90 minute mash.
Sparge was double batch (13 lts. then 10 lts). All readings are prior to mixing and the pipette sample was cooled in ambient temp water prior to reading.

Runnings off the mash Brix *18 (1.075)*

1st sparge Brix *9 (1.037)*

2nd sparge Brix *4 (1.017)*

combined runnings Brix *9.4 (1.038)* Beersmith predicted SG of *1.037
*
Volume into kettle *32.5 litres* (Beersmith predicated *31.76 lts*.)

Kettle bought up to boiling Brix *9.2 (1.037)*

15 minutes into boil Brix *9.4 (1.038)
*
30 minutes into boil Brix *9.6 (1.039)* First Hop Addition...

45 minutes into boil Brix *10.4 (1.042)* Notice gravity leap after hops added.

60 minutes into boil Brix *10.8 (1.044)* 

75 minutes into boil Brix *11.0 (1.045)*

80 minutes into boil Second hop addition

90 minutes into boil Brix *12.2 (1.050)* Flame Out. (Beersmith predicted *1.048*)

30 minutes after flame out - Brix *12.2*

Wort volume post boil *24 litres.* 





Boil was a very vigorous 90 minutes. Although my 'equipment' is set at 12% evaporation during boil a loss of 8 litres (15%) is quite usual. If I had achieved the set volume of 25 litres - efficiency into fermenter would have been 84.2%

Hope this is of some value to you Pat.

Cheers, Hoges.


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## Ross (11/4/07)

Those readings look spot on Hoges  

cheers Ross


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## PistolPatch (12/4/07)

My computer was playing up last night (the night before it was the thing on the end of the computer that was playing up :unsure so I haven't had time to read the above thoroughly though I did get 11 hours sleep!

I saw Trent's post saying he had the same thing happen as I did. This made me think that boiling some extract (which has already been boiled) may produce a different result than boiling actual wort. But now Hoges has given us some detailed figures that contradict mine and Trent's. Trent's figures turn out as expected. Man, I am perplexed!

Thanks a heap Hoges for doing all the above so well and thanks to all the others above (and one in a PM) that are prepared to do the same on their next brew. Can't wait to see what everyone comes up with.

I wonder if we end up getting two sets of different figures??? How bad would that be - OMG!

LOL
Pat

P.S. Special thanks to Trent too. It's great to know that at least one other person out there is having the same problem. For a while there I was even thinking I wasn't an insane measurer, just an insane AHB poster  If it turns out to be the former as well then at least Trent and I can have meetings. Super!


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## Ross (12/4/07)

Pat,

I honestly believe your strange findings are measuring inaccuracies.
You are going to struggle with a refractometer to get consistant/accurate enough results at the level you need for the experiment without a controled way of cooling like Hoges has used. Despite the fact they are temperature adjusting, i find the most accurate measurement is when the sample has just reached approx ambient temp. If you leave it too long, the figures change - don't ask me why, coz i don't know, but I guess it could have something to do with the break etc seperating out in your sample.
If you want accurate easy to read figures, draw your samples at various stages, cool them all to the same temp & use a hydrometer. Edit; Also, make sure all your wort volumes are measured at boiling & are accurate.

I believe most people are only interested in getting consistant results on their system & hitting the final gravity as expected. To this end, i know that a 90min boil on my system raises the average wort by 2.2brix. I simply make any adjustments, if necessary, at the beginning of the boil.



Cheers Ross


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## FNQ Bunyip (12/4/07)

MMMMM well I've been following this because I get differant results as well ...so I just gave up trying to work it out and don't worry with any mesuring at all.. 


I fill my kettle to about the same each time 
drop the grain in / pull it out 
Boil for 1hr / cool 
drain into fermenter and end up with about 24-26lt ( marked on fermenter) 

tastes sweet/ feels sticky , 
add yeast wait a week and drop into a keg

6 glasses later I know if its about right or not ...


might do another brew on the weekend and will get the hydro and refrac out and see what I get ,, Just for you Pat.. 

:beer:


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## brendanos (12/4/07)

Ross said:


> If you want accurate easy to read figures, draw your samples at various stages, cool them all to the same temp & use a hydrometer. Edit; Also, make sure all your wort volumes are measured at boiling & are accurate.




This is pretty much what I did yesterday, drawing off a sample pre boil and post boil (volume is that collected in fermenter). Hot samples were chilled, then brought to an average temp of 21C over half a day. I take the easy (cheats?) route and set the volume of wort in ProMash, then adjust efficiency til I hit the gravity reading from a hydrometer.

Pre boil, 18L @ 1.035 (78% efficiency)
Post boil, 13L: @ 1.046 (74% efficiency)

For a 28% reduction in volume, 4% loss from kettle to fermenter seems pretty tidy to me. I would attribute it to losses to hops (65g, mostly flower) and break material, though these losses are significantly better than I previously would get without the hop sock. FTR I was expecting 74% efficiency.


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## Trent (12/4/07)

When I usually take my pre boil readings, I take them at ambient temp, so I am fairly sure they are right, but am happy to be proven otherwise (I know I am too far away for anyone to actually do this, but it just means I am not saying I am 100% correct).
BUT, reading Brendanos' post just above me here is where I find my efficiency goes a little haywire, although Brendanos seems to be happy with it

18L at 1.035 can be translated to 18 x 35 = 630 gravity points.
If those 630 gravity points were still there in the 13L, it would be 1.0485 
(630/13 = 48.46)
In reality, he has 13 x 46 = 598. 

Where did those other 32 gravity points go? Feel free to do the maths yourselves, and I am also open to the possibilty that brendanos hasnt measured accurately and is .7L out (which will prove my argument incorrect), but this is fairly well what I come across most brews. At the end of the day, I am quite happy to trust my system is going to hit the right gravity at the end of the boil/chill/etc.., and it usually does. I just dont base my efficiency on my preboil gravity, cause then I would be hitting below my targets all the time (I think). 
Brendanos was expecting 74%, and he hit it - postboil. Thats the way I play the game anyway. But I still think that there must be some sugars that boil off. If you put your face over the steam (okay, WAY above the steam) when you are boiling and peeking in, then take it away and let the condensation evaporate, does it feel a little sticky? I find it does.
Sorry - rambling a little bit here. Anywayas previously stated, I usually hit my targets, just my preboil and postboil efficiencies dont correlate.
All the best
Trent


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## lucas (12/4/07)

Trent said:


> Where did those other 32 gravity points go?


From what brendanos has said and what you've said I can identify two main possible sources of error.

1. brendanos post boil volume measurement is taken in the fermenter, so as he has identified there will be a loss of wort to hops/deadspace etc, wort containing gravity points. there's also the chance that the marked volumes on his fermenter dont exactly correlate to his measured volumes in his brewpot.

2. expansion/contraction of the wort at different temperatures. if all reading are taken at boiling this can simply be ignored, but if your pre boil volume readings are before boiling and the post boil volume readings are some time later then the two figures cant be directly compared. the quoted 4% expansion is between boiling and some other temp (off the top of my head it's either 4 or around 20 degrees, I cant say for certain), so applying it to volumes of wort that is between these two temperatures isnt going to be a magic fix.

there's also limit of reading errors, try fudging some of the less significant digits of the readings and see how easy it is to create or lose gravity points, but work is over so I'm heading home rather than harping on about that right now


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## brendanos (12/4/07)

I'd be willing to wager most of those 32 gravity points would be found firstly in the compost bin amongst the hop matter, and secondly in the bottom of the kettle (with the cold break) and the sock that I ran the beer through just incase any of the denser break made it out of the kettle. It seems fairly likely that while this cold break material is suspended in the liquid (pre boil) that it would contribute to some of the density of the liquid aka the specific gravity. FTR I did mix the sediment back in when taking SG readings.

I'm not dismissing the possibility that some more/less dense non-water particles evaporate off during the boil (in fact this is obviously true, as it is one of the many functions of the boil, but what effect they have on the overall density of the liquid I can't really speculate), I haven't seen proof either way, so I'm happy not to take a side. I'll help narrow it down though, in our homebrewed version of scientific evaluation.

A refractometer is in the mail, so next time I should have a more detailed set of data.


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## Trent (12/4/07)

Brendanos
I usually account for my trub, etc... when calculating my efficiency, so it is quite possible that is where those 32 points are, if you dont calculate the .7L that would be needed to take up that slack. As I have said, if I get 23L into my fermenter, I know that my pickup tube leaves 2.5L in the kettle, so I calculate my efficiency on 25.5L post boil. As I said earlier, if you havent taken into account that .7L, or didnt measure accurately, then my argument is out the window! Re-reading your post now, it is obvious I misread it the first time, as I didnt realise you didnt count the kettle losses. Anyway, it matters not all that much to me, I just want to put forward my experiences, and show everyone that PP isnt insane (or that I am), and see if anyone else has had similar occurences. I only used your post as an example, because your numbers were higher pre boil, as I usually experience.
It appears at least 2 of us go through this phenomenom, and not many, if any, others do. I am happy to write it off as a system specific anomaly, but will look forward to more detailed data. 
All the best
Trent
PS Lucas - I take into account the 4% expansion of wort at boiling, though when I take my readings, the wort is usually at ambient, and the 4% is not an issue. Off the top of my head, I think the expansion is between 4C and boiling, but I am not certain either! I know it is easy to fudge, and/or make mistakes, but it happens regularly enough to not surprise me. T.


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## brendanos (12/4/07)

lucas said:


> there's also the chance that the marked volumes on his fermenter dont exactly correlate to his measured volumes in his brewpot.



Brewpot markings/measurements were made by running set volumes from a fermenter into the kettle a few times until mean/consistant levels were reached, so this should rule that one out.



lucas said:


> 2. expansion/contraction of the wort at different temperatures. if all reading are taken at boiling this can simply be ignored, but if your pre boil volume readings are before boiling and the post boil volume readings are some time later then the two figures cant be directly compared. the quoted 4% expansion is between boiling and some other temp (off the top of my head it's either 4 or around 20 degrees, I cant say for certain), so applying it to volumes of wort that is between these two temperatures isnt going to be a magic fix.



Both readings were taken at 21C 16ish hours later (during which time they were rested in sealed mugs and sat in a water bath with a third "pitched" sample), so unless I'm missing the point (in which case I'd love to be clued in!) I think they should be relatively comparable.

I will concede that taking the readings off the hydrometer was a painful task, and the less than desirable accuracy of the readings means that I wouldn't overanalyse them/extrapolate too far with regards to the comparisons. I would definately prefer a larger scale to work with, or another means of consolidating values (refractometer!).


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## PistolPatch (12/4/07)

My goodness! Now everyone's writing long posts! Ross that has to be the longest post you have ever written - lol!

So proud of myself - I thought I had solved the 2 different sets of figures problem but my idea actually makes things worse - agh! (I was thinking that Trent and I seem to take our volume readings just off the boil rather than whilst boiling. Hard to take ruler measurements whilst boiling but it seems to read reads 1.5 - 2cm higher anyway so this is no help. Grrr!) My gravity sample though is taken just before I turn the gas off to get my volume reading so the wort is well-stirred.

I just worked out the margin of error we are looking for on my last set of figures in case this does help. To match my final efficiency, my start of boil efficiency should have either had 3lts less of wort (2cm on my ruler) or 0.55 less Brix. I don't think either of these can be put down to the way I'm reading the instruments. Also, if I am misreading the instruments then I am reading them incorrectly at the same time on each brew whether I'm having a beer or not :blink: 

Re Ross's comments on reading the refractometer I agree. Read as soon as at ambient otherwise it continues to steadily climb probably as the water content evaporates or something.

It also looks like Trent and I aren't the only poor buggers getting this problem. Just found the following thread on Norther Brewer. Unfortunately the discrepancy hasn't been resolved there either. Great 

I so wish we could get the figures to match pre and post-boil then an AHB standard would be really easy.

Looks like Ned has been having troubles as well and it will be especially interesting to see what figures he pulls on the weekend as his kettle is a different shape from mine  Good on ya Ned! If he has the same problem then kettle shape is not going to be the answer.

By the way, I use a 70lt Robinox with 45cm diameter so lots of surface area and very high evaporation rates. I wonder if Trent has a similiar kettle to mine or maybe Ned's???

This is worse than the worst brain teaser puzzle - quite infuriating! I have no patience for brain-teasers. I just look the answer straight up. It's much quicker! Waiting for all these figures is a nightmare - lol.


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## lucas (12/4/07)

brendanos said:


> Both readings were taken at 21C 16ish hours later (during which time they were rested in sealed mugs and sat in a water bath with a third "pitched" sample), so unless I'm missing the point (in which case I'd love to be clued in!) I think they should be relatively comparable.


yes, you've measured both the gravities at the same temp and those by themselves are total comparable. but the point I was getting at is that unless you measure your volumes all at the same temp they are not directly comparable. if you measured pre boil volume at mashout into kettle temps (60-ish), mid volume boil at 100C and post boil in the fermenter (80-ish assuming you're no-chilling) you'd need to know some more constants to draw comparisions. ie. (preboil vol)* (expansion factor @ 60) vs (midboil vol * 1.04) vs (postboil vol)* (expansion factor @ 80)

honestly, I dont measure things with this much accuracy myself yet as my efficiency is still a bit all over the place, but when I'm trying to explain something I like to think about things and an analytical manner


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## Trent (12/4/07)

PP
My kettle is a legally acquired 80L keg, one of them almost oval shaped ones. My evaporation rate is about 4L per hour on average, so it would appear that has little to do with it (I have to keep the lid 2/3 on during the boil to keep a full on rolling boil)

Lucas
I actually (usually) mash and sparge one night after work, and keep the lid on the kettle, and then the next night I come home and set the flame on. The qort is usually around ambient, judging by the feel of the kettle, and if it is higher, would rarely be more than 30C or so, and as such would have little effect on the refractometer reading. When I take the reading, I stir the hell out of it with a paddle, to redistribute all the sugars, that take some of the wort and measure that. Postboil figures are taken direct from the fermenter pre pitching yeast, and is usually between 18 and 20C (temp it comes out of my chiller). Too many variables, and obviously, after checking the thread PP found, it happens to some people, but not most. At least I dont LOSE gravity points! Knock on wood.
All the best
Trent


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## PistolPatch (12/4/07)

[Edit: I've tried to think through all measurement problems below but I will have missed some. If anyone has improvements to the following or sees some errors, please let me know. Quite amazing how much writing it's taken though. I honestly thought it would only be two paragraphs! My allowing for hops below is a bit over the top but at least it will standardise the measurments.]

*Template for Measuring Start of Boil and Post-Boil Efficiencies*

For those of you who did put their hand up to post their figures, I've jotted down some notes (very pedantic ones) on what readings to take and how to take them. I've done this not only for guys who are a little unsure of how to take their readings but also to provide a standard method amongst all of us.

I think it would make it really easy for everyone to see and analyse the figures you provide if you copy and paste the last bit of this post but substitute my figures for yours.

I have also included some instructions so that when an experienced guy sees your raw figures they will be able to copy your post and convert them quickly to efficeincy figures.

We need a minimum of 2 readings, preferably using a hydrometer, plus the weight of your grain bill - not its actual composition.

*How to Measure Start of Boil Efficiency

1. Hops* If you have hops to add at the start of the boil then add them after taking the following volume and gravity measurements.

*2. Gravity* When wort comes to the boil use a coffee mug (saves your hydrometer tube warping) to take enough wort to fill your hydrometer tube. Cover it with Glad Wrap to avoid evaporation and then let it sit in a sink of cool water. Stir it from time to time and when it is at 20 degrees, pour it into your hydrometer tube and take your reading. Write down your reading to 3 decimal places e.g. 1.040

(Some hydrometer tubes use 250ml of wort for a reading. If it is this high then pour your sample back into the kettle and add these mls to your volume figure in 3 below. Most commercial hydrometer tubes only use about 100 mls so, if you have the thinner tube then I wouldn't worry.)

If using a refractometer, take a tablespoon of wort, dribble it onto the refractometer and take the reading five minutes later. Write down the Brix reading and multiply it by 4.1 then add 1 unit. e.g a Brix reading of 10.0 would equal 1.041. Post this to 4 decimal figures so people can see that you used a refractometer.

We will call this figure, 'Gravity at Beginning of Boil.'

*3. Volume* Turn off your heat and wait one minute, then take your volume reading. Write this down in litres as close as you can get to 1 decimal place e.g. 30.6lts and then multiply it by 0.96 to allow for wort expansion, (30.6 x 0.96 = 29.376) to get the figure we are interested in. Convert this to 1 decimal place and publish this figure. In this example it would be 29.4lts.

*Final Efficiency

1.* Check that your fermenter is correctly graduated. Commercially bought ones should be.

*2.* Just before the boil ends, take another sample using your coffee mug or tablesppon in the same manner as you did for your Start of Boil gravity reading. This sample will end up down the drain so if it is of significant volume (eg 200 mls or so) then remember to add these mls in the step below.

Once cooled to 20 degrees, write the figure down to 3 or 4 decimal places depending on whether you used a hydrometer or refractometer. We will call this figure, Gravity At End of Boil.'

*3.* I am going to assume you are doing an ale. Chill your wort to 20 degrees (+/- five degrees) and then syphon it into your fermenter. Stop syphoning when the wort starts to run cloudy or when you have reached the desired volume into your fermenter. Write down how many litres you scored into the fermenter. Have a crack at guessing it to within 100mls though this is of course not possible. This will be _Volume 1._

*4.* Now you will be left with your trub in the kettle. If you have a hopsock, take it out. You should now have an empty kettle. Pour all that remains into a graduated jug and then write down the mls. This will be _Volume 2._

*5.* If you used a hopsock, then record the total amount of hops you have added into your brew in grams and then convert this to mls. For example if you added 90 grams of hops then write down 90mls. This will be _Volume 3._ If you didn't use a hopsock and your hop debris remains in the kettle then your Volume 3 figure will equal zero.

*6.* Add Volumes 1, 2 and 3 and then round this figure to one decimal place. This will be what we will call your 'final volume' which is a more accurate description for our purposes than volume into fermenter.

*Grain Bill*

Write down how many kilos of grain you used in the brew to two decimal places. e.g. 5.25kgs.

That is all you need to post here. The advanced guys will use Beersmith to convert your figures into a compatible efficiency. If you are not one of these advanced guys then you can skip the next section and jump straight to the bit that says, 'These Are My Figures.'

*Advanced Guys*

I think, for the sake of simplicity, that a single type of grain should be assumed. I reckon we should choose a grain that has a potential SG of 1.038. For example if one of the guys above has posted they used 5.25kgs of malt then we plug into Beersmith 5.25kg of Weyermann Pale Malt. Most base malts are up around there though for the sake of this exercise is everyone happy to use that malt?

I think we should use Beersmith as more people seem to have it. Also, regardless of the lauter tun deadspace figure, it makes no difference if you plug the figures into the Efficiency Into Boiler section or the Efficiency Into Fermenter section.

I also think that the term, 'Final Efficiency,' avoids a lot of confusion and could maybe even be a candidate for an AHB standard. (Some advantages and some disadvantages here.)

So, if you see someone has posted their raw figures, can you copy their post and whack the following in at the end?...

Efficiency Into Boiler = _x_%
Final Efficiency = _y_%

I'm going to whack my figures in below, (have adjusted my volumes to 4% shrinkage instead of the 5% I originally used and had a guess at hop figures) but I think it would be better for the thread if one of you guys copied the last part of my post and added the efficiency figures. This would be a lot better than me doing 3 posts! Just quote the last part of this post and whack your figures in.

_The rest of this post shows what can be posted by anyone._

*These Are My Figures...*

Brewer: PistolPatch
Grain Bill Weight: 3.78kg

Volume at Beginning of Boil = 32.4lts
Gravity at Beginning of Boil = 1.0295

Final Volume = 25.8lts
Gravity at End of Boil = 1.0336


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## Screwtop (12/4/07)

How can you write such long posts Pat  

Faaark! I can't even read em, wish it was the same as email, any long winded emails I receive, I just hit the delete button. I'm here for a good time not a long time! Anything that long has to be far to serious, leave that megaswill shit alone, it does funny things to you around the Easter full moon.


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## brendanos (12/4/07)

lucas said:


> yes, you've measured both the gravities at the same temp and those by themselves are total comparable. but the point I was getting at is that unless you measure your volumes all at the same temp they are not directly comparable. if you measured pre boil volume at mashout into kettle temps (60-ish), mid volume boil at 100C and post boil in the fermenter (80-ish assuming you're no-chilling) you'd need to know some more constants to draw comparisions. ie. (preboil vol)* (expansion factor @ 60) vs (midboil vol * 1.04) vs (postboil vol)* (expansion factor @ 80)
> 
> honestly, I dont measure things with this much accuracy myself yet as my efficiency is still a bit all over the place, but when I'm trying to explain something I like to think about things and an analytical manner



Thanks for clearing that up, I hadn't realised what you were referring to earlier, and yeah it's probable that thermal expansion could account for quite a significant difference in volume (possibly even enough to explain a large part of the apparant 4% variation in efficiency). Volumes were measured after lautering at 80ish and in fermenter after chilling to 22-24C.

Cheers
Brendan


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## lucas (12/4/07)

PistolPatch said:


> If using a refractometer, take a tablespoon of wort, dribble it onto the refractometer and take the reading five minutes later. Write down the Brix reading and multiply it by 4.1 then add 1 unit. e.g a Brix reading of 10.0 would equal 1.041. Post this to 4 decimal figures so people can see that you used a refractometer.


Ok, so I've only read down to here so far (my god you can write PP), but I'll throw in my opinion that people measuring in brix/plato should post their figures in brix/plato. there are several different ways to convert between brix and SG and most of them dont completely agree with one another. I'd leave the conversions up to the reader to ensure that nobody is using a different conversion method without mentioning it.


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## PistolPatch (12/4/07)

I'm on the phone to Screwtop at the moment but I reckon this thread should favour new brewers. If people follow my decimal point system and the simple multiplication written there then the experienced guys can work back should they want to convert to Brix. Fair enough?


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## Screwtop (12/4/07)

lucas said:


> Ok, so I've only read down to here so far (my god you can write PP), but I'll throw in my opinion that people measuring in brix/plato should post their figures in brix/plato. there are several different ways to convert between brix and SG and most of them dont completely agree with one another. I'd leave the conversions up to the reader to ensure that nobody is using a different conversion method without mentioning it.




I take all measurements in Besser Blocks, can't be bothered with Brix


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## chris.taylor.98 (12/4/07)

I was very confused for a long time over efficiency calculations.

The model that I finally settled on ( that made sense for me anyway ) was to work on a point system, multiplied out by the volume.

The theory behind this system is that if we take a quantity of liquid and measure the density of sugars in suspension ( ie gravity ) for example 2 liters at 1.048, then if we dilute the solution with water ( lets say to 4 liters ) the gravity is reduced by the same amount ( ie it will now be 1.024 ). i.e the density is directly related to the amount of sugars and the volume, and this relationship will not change unless you actually take some of the sugars out of the system.

This way you can calculate the expected gravity of all your run-offs ( if you batch sparge like I do ) and also work out your conversion ratio.

This method is actually very simple when it comes down to it (despite me trying my best to make it long winded and complicated), and takes away a lot of the mystery surrounding the efficiency calculations.

Basically you start with the theoretical maximum gravity that you could get if you had an efficiency of 100%. ( So lets say it is 1.068 for example ) and you factor this with the number of liters that you expect ( assuming that there are no loses to trub or dead spaces etc ) lets say 25 liters. To do this take the last 3 digits of the gravity reading ( lets call it "points" for want of a better term ) and multiply it by the number of liters. In this case:

25 x 68 = 1700

Now this figure represents the theoretical maximum amount of "points" what we are able to extract if we could get 100% efficiency and there are absolutely no losses.

So now to determine our actually efficiency we just calculate the number of "points" that where extracted after sparging, by measuring the gravity of the wort in the boiler ( lets say 1.052 or 52 and 23 liters ) which ends up with:

23 x 52 = 1196

So our efficiency is 

1196/1700 = 0.70 ( or 70% )

Now the fun part of this method is that we can even work out an approximate conversion % if you are batch sparging, as well as the expected gravity of each of the batches ... yes I know that brewsmith and all those other tools already do this for you ... but this way you may even get to understand it a bit.

I have a horribly rough spreadsheet that I use to do all this if anyone is interested, might even get around to cleaning it up for mass consumption one of these days 

Some other points on efficiency calculations:

i) Its only a theoretical model and will never represent the real world exactly. To start with, if the grain that we are mashing varies from the grain that they used to determine the extract potential, then the calculations are not going to match exactly even before you take into account your process, and your equipment ( ie don't get too carried away about it being spot on to what you have calculated, as this rarely happens ).

ii) Low efficiency is not a sign of lack of manliness, and there is much to say that you might end up with a better beer at the end of it. In fact some brewers have reported good results by only taking the first runnings from the grains, and not adding extra sparge water at all ( about 50% efficiency ). I usually aim for around 70%.

iii) The only real benefit of accurately knowing your efficiency is to be able to plan your recipe to give you the gravity that you need for the beer you are making. Once you can consistently predict this, then you don't really need to worry about it. 
The "cost" of not getting that extra 10% out of your system is probably only a couple of dollars in grain, and mostly likely will lead you to doing stupid things like over sparing and ruining many potentially fine batches of beer ( and yes I am talking from experience here ).

Cheers

Chris


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## bayWeiss (13/4/07)

I think this whole thing is really getting overcomplicated... and it does not have to be.

In regards to the problem question... there is only one question that is being asked.

Where did the sugar go from the time period of "boil begin" to "boil end"? With this being said, grain type used, and *absolute* efficiency values are irrelevant.

Now, the most controlled way of figuring out what is going on is to have a very controlled test. This means in essence, that you can not brew beer to test this, because there are too many variables and you would probably ruin your beer in trying to test for the "yield = loss of sugar". 

As I mentioned above (if you read back some pages) you need to have a test with a controlled sugar solution. The only part that really needs to be controlled, are the measurements of the three variables [volume and gravity and temperature]. This entails homogenous temperature readings and EXACT measure of volume at that particular temperature. Also, the gravity reading needs to be taken at that temperature.

That is it... there are no hops involved, no boilovers, and no volume losses due to break material.

You are only going to get to the bottom of this problem by doing something similar to what I suggest, or, you will need a sample size of 1000 brewers or so to overcome random error creeping in.

cheers!


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## PistolPatch (13/4/07)

bayWeiss said:


> I think this whole thing is really getting overcomplicated... and it does not have to be.



Sorry Chris, I haven't digested your post as yet but will have a look tomorrow.

Meanwhile....

Bayweiss, I don't agree. I spent considerable time tonight converting into words in the technical post above what could be conveyed face to face in five minutes.

Yeah, it is simple but it is also not that simple. There were five or so posts of God knows how many words today just analysing one person's set of figures. This costs both the writers and the readers a heap of time.

I have had a crack at establishing some clear standards to adhere by in taking readings. Is this not a good idea or should we continue taking up time trying to nail down how every individual takes their readings?

Your suggestion of measuring an extract or sugar solution I have already refuted. The stuff has already been boiled so cannot possibly give us an informative answer. The low volumes in the proposed experiment would also create a higher degree of error.

We are dealing with real life stuff and this means grain.

So, I think the technical post above might well be worth a second and very considered look. If anyone can shorten the post, I'm all for suggestions. Personally, I think it would be quite difficult to shorten it to a standard that encompasses everyone.

Spot,
Pat


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## bayWeiss (13/4/07)

PistolPatch said:


> Your suggestion of measuring an extract or sugar solution I have already refuted. This stuff has already been boiled.
> 
> We are dealing with real life stuff and this means grain.
> 
> ...



I am not sure how the argument of whether something has been boiled already or not has to do with measuring sugar in a solution. [you get an accurate volume measurement (means taking temp into account), and an accurate gravity reading] Sugar is sugar is sugar... sure, there are different types of sugar, but I do not see what relevance this has to checking the gravity.

The phenomena should be boil-time invariant. You should be able to perform a test from 60 minutes to flameout, or 45 minutes to 15 minutes. You can determine if it is boil-time variant by taking a large enough sample size of measurement during the boil, and you will see something non-linear.

It is my belief, that the whole thing is random error, and you will not see a pattern... just like I do not see a pattern really of trials from the previous posts.

oh, this is frustrated bayWeiss....  

:beer:


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## PistolPatch (13/4/07)

OK, one last refutation of the measuring sugars idea.

Let's say that we do conduct this experiment.

Regardless of what result it gives, it will not explain why Trent, I and at least another two get the readings we do when making an all-grain brew. Exactly the same instruments are being used in either test.

If anyone can argue against that logic then they have me buggered.

Doing such a test does however have some merit. It would establish if there is a difference between measuring previously boiled sugar solutions and real life grain solutions.

This would be very interesting but still doesn't solve our problem.

Anyway, I'm out of here for a few days. Hopefully I'll be coming back with a big smile on my face - say your prayers guys


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## bayWeiss (13/4/07)

In all honesty PP if you are troubled with the idea of sugar or extract, then you can do the experiment with a small pilsner mash or something...

I just suggest you keep the water volumes low for ease of handling, and quickness of cooling/measuring. Also, keep the hops out of it, and mix the cooled wort before taking measurements to keep sugar water stratification non-existent.

cheers!


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## PistolPatch (15/4/07)

Chris Taylor said:


> I have a horribly rough spreadsheet that I use to do all this if anyone is interested, might even get around to cleaning it up for mass consumption one of these days



That was an interesting post Chris and I'd certainly like a look at the spreadsheet. Thought your comments at the end were very good too.

I was hoping that a few people may have brewed yesterday and added some figures. All we have so far are Hogan's and mine. I've converted these figures to and posted them below using the standard I proposed in Post #59 - the one that no has read 

*Figures to Date*

Brewer: *PistolPatch*
Grain Bill Weight: 3.78kg

Volume at Beginning of Boil = 32.4lts
Gravity at Beginning of Boil = 1.0295

Final Volume = 25.8lts
Gravity at End of Boil = 1.0336

Efficiency Into Boiler = 80.1%
Final Efficiency = 72.6%

Brewer: *Hogan*
Grain Bill Weight: 4.77kg

Volume at Beginning of Boil = 32.5lts
Gravity at Beginning of Boil = 1.0370

Final Volume = 24.0lts
Gravity at End of Boil = 1.0500

Efficiency Into Boiler = 79.9%
Final Efficiency = 79.7%


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## Corny (15/4/07)

For those using a dip-stick to measure volume: TEMPERATURE

Made a dip stick by adding 5L at a time to my vessel and marked the stick. Then made a really nice job of it all sealed and laquered. Filled the HLT to the required level/amount. Heated my strike water and checked the volume - had an extra litre - of course expansion.


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## lucas (15/4/07)

Brewer: *Lucas*
Grain Bill Weight: 6.17kg

Volume at Beginning of Boil = ~ 31.5lts
Gravity at Beginning of Boil = 10.75P = ~ 1.043

Final Volume = ~23.0 - 25lts (couldnt measure it very accurately yet due to hop sock, just below the seam of the keggle)
Gravity at End of Boil = 14.75P = ~ 1.060

edit: looking at the numbers some more I seems to have defied physics in the opposite way to you PP  That said, my measuring stick is only calibrated in 2L increments so I'm welcome to the possibility my measurements are crap


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## Thirsty Boy (15/4/07)

A couple of quick points. Not really any answers but some things to think about.

*Measuring*

Dipsticks - It seems that a lot of people are measuring with dipsticks. There has been a lot of talk about thermal expansion of wort at different temperatures. But none about thermal expansion of dipsticks, or of kettles. Calibrate that dipstick with cold water and then stick it into boiling wort... not gonna be accurate anymore. Your kettle is also going to expand and contract. Dont know the amounts, dont know what effect it would have. But i bet it has one, and we are only talking a couple of % here and there for our mystery figures. Hell, what th dipstick is made of will make a difference from brewer to brewer.

Calibraton - Learned this lesson the hard way. The set of measuring jugs I bought was out of whack and by a good 15% too. I ended up having to calibrate my whole setup using a 500ml measuring cylinder. In this thread so far, different people to different degrees, seem to be mixing up their measuring tools. To be consistent, everything you use needs to be calibrated from the same base measuring device. Kettle, Dipstick (which is probably a bad tool for accuracy in the first place) measuring jugs, fermentor.... the lot. If you want consistency AND accuracy, better make the base measuring device a peice of lab equipment. Better yet, a really accurate set of scales and 100 litres or so of distilled water.

Reading - When you are taking your volume reading etc. How accurately can you read your intruments, even if they themselves are accuarate? I've used a dipstick a few times and just to see how accurate it was, I did a rough experiment. with the liquid on the 5litre mark I added 100ml and asked my wife to tell me the volume in the kettle -- 5litres, and thats what I would have said too. So I played around using random volumes in and out, and the wife could not tell volumes with any better accuracy than + or - 100ml (and thats being generous) Thats a 200ml range on a measureing device with a gradiation at 1000mls. That means that my measurements are really only accurate to within + or - 10%. That error flows accross to everything else you are calculating. Your figures can only be as accurate as the LEAST accurate figure you obtain. And I dont know about you, but when I read my hydrometer, anything more accurate than 1.041 , 1.042 is just kidding myself and when we are talking the difference between readings of say 1.038 and 1.035 the inability to read down to the 4th and 5th point becomes really significant.

Potential Extract - You cant just quote weight of grain bill. Potential extract can have a real effect on final figures. assume 1.038 and its not, then your figures will be out. At work our extract figures can vary by several % from batch to batch of the same grain from the same maltster. You have to quote your expected efficiency for the grain you actually used. If a recipe recipient uses different grain, its just going to be different and they need to take it into account.


But, to not just point out negatives - I will do the controlled experiment that has been suggested. I will however do it with AG wort to avoid the "boiled or not" issue. I will use volumes that are small enough so that they can be fully decanted into vessles calibrated with lab equipment in order to work out volumes; and all the samples will be taken to work and run through our digital density meter.

I will also ask one of the brewers if its possible to lose extract during a boil just to see what he says.

Like I said, no answers, but a few more things to think about before any conclusions get drawn.

BTW. IMHO - efficiency into the kettle is the thing to consider. Thats what pro brewers use if they are swapping recipes, thats what BYO and Zymurgy use. A lot of brewers get recipes from those sources, I think we should stay consistent with them. My $.02 anyway.

Thirsty


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## PistolPatch (16/4/07)

*LOL Lucas* Yeah I noticed that! If you did end up with 23 litres then you would have had no efficiency drop. If 25, then you would have had an efficiency increase! You never know, you mightn't be the only one who gets this - lol. Did you work out your final volume in the end BTW? If so we can whack your figures into the list. Thanks mate.

*Ah Thirsty!* So well-written mate but unfortunately you must have missed a few critical posts. Oh well, you get that 

I think everyone here would be happy to use Efficiency Into Boiler figures as a standard but a few of us are finding our efficiency dropping during the boil by up to 10%.

Hence, what we are trying to gather now are some figures to try and see how many people are having this problem and then hopefully discovering why. For the purposes of determining this, potential SG is irrelevant and the 1.038 has been picked arbitrarily just to make it quicker to see if peopole are getting a drop or not.

A lot of points you mentioned others have brought up already but the thermal expansion of dipsticks and kettles is a new one. Unfortunately this point doesn't help with the problem either. We would need a contraction to occur at high temps not an expansion. Would have been nice if that was the answer but it's not.

Be great if you can throw in your figures though. We certainly need a lot more and I think these are the key to this thread for the moment.

I'm going back to bed now with my flu which is the only thing I've been in bed with this weekend.

<_< 
Pat


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## Trent (16/4/07)

Gday all
Just spent the weekend at a mates house, and he is a full time brewer. He was telling me that when he brews at home, he gets 90% efficiency into the kettle, and his overall brewhouse efficiency (postboil, and taking into account the trub, etc..) is usually between 72 and 75%. That is the efficency he quotes when people ask, and that is the way I base my eff. too. I think that is probably the easiest way to quote it, as it will obviously be the lowest number, but feel free to quote preboil eff (mash efficiency) as the way to go. I will just keep basing all my stuff on brewhouse effiency, as that it what allows me to work out my recipes. At the end of the day, thats the only reason we need to use efficiencies anyway.
All the best
Trent


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## Thirsty Boy (16/4/07)

Pat,

I understand that the potential SG has nothing to do with the amazing shrinking efficiency problem. But it does have to do with the ability to translate recipes from brewer to brewer. I made that point more towards the original question posed in the thread, rather than the perplexing side issue.

On the perplexing side issue however.... Actually I didn't miss the points you mentioned. I know a number of the things I talked about have been covered, I just dont think that a lot of them have been as well addressed as you say they have.

I have seen a few posts where calibration was mentioned, but no one has made a comprehensive statement that convinces me that their setup has been really well calibrated. Not saying they aren't, I just haven't seen anything that says they are. I also haven't seen anyone talk about the accuracy with which they can read their instruments, not just how accurate their instruments are. The ability to factor in consistent margins of error is critical in any scientific experiment. 

I mentioned, I am unable to read my dipstick to a certainty of more than +/- 100ml or my hydrometer to better than 3 figures;

*so to make an example*: Lets say I read my pre-boil volume to be 23litres @ 1.038 That gives me 874 points of extract. BUT in reality I have 22.9 litres at 1.0375 for 859 points of extract.

I conduct my boil and at the end should still have 859 points of extract, so I take my measurements to see. In reality I have 20.1 litres at 1.0427 (859 points) but what I read is 20.0 litres at 1.042 for 840 points of extract.

So I have magically lost 34 points of extract in the boil. Thats 3.9% Reverse when I read the highs and lows and I am working with an accuracy of around +/- 4%.

Add in measuring pre-boil with my dipstick that is calibrated to read ever so slighlty high and then measure my post boil in my fermetor that reads ever so slightly low... and suddenly 10% variations dont look that far out of the ball park.

Thats not being unrealistic either, the figures I quoted are pretty close to the BEST I could do for accuracy. 

The +/- factor, that could be caused by a number of things, is my main point. Not if the expansion or the mis-calibration effects the results in any particular way, but that the expansion/contraction or whatever introduces _uncertainty_ that needs to be accounted for.

You are of course right when you say that we need more numbers to help figure this out, but to be honest, I just dont think that the majority of homebrewers out there are measuring things in an accurate enough way that you are going to get conclusive results with the sort of sample size you are likely to get.

I really tend to believe that the shrinking efficiency is a matter of systemic error in measurment. Sorry.

*To be less of a party pooper though. I am happy to help prove myself wrong.*

Next time I brew my house ale, I'll make the batch a bit bigger so I have 4 litres of AG wort with which to conduct as tightly controlled an experiment as I can. I will heat it to nearly 100C and tap it off into a small no-chill. After I have finished my regular brew day, I'll geek out on the 4 litres. 

-Everything calibrated from the same schot duran measuring cylinder. 

-All volumes taken at the same temperature and measured by fully decanting the whole kettle into the measuring container

-All gravity samples taken to my work and run through the serious arsed desktop density meter

I still doubt if I'll be able to get any better than +/- a couple of percent, but I will do my best.


I will also go talk to the guy who runs our lab brewery (mate, I drool when I see that lab brewery, it is every hombrewers wet dream made real) and find out whether dissapearing extract is possible in his view. His whole job is to conduct mashes, boils and fermetations to 3 decimal places in accuracy and consistency. If it happens, he'll know about it and be able to tell us how to calculate it.

Dont hold your breath waiting for me though, its gonna be weeks at least till I brew again and I wont be on the right shift to talk to the lab guy for a couple of weeks either. Sorry.

Damn.... I write posts longer than Pat does.

Thirsty


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## lucas (16/4/07)

PistolPatch said:


> Did you work out your final volume in the end BTW? If so we can whack your figures into the list. Thanks mate.


It's in a nochill cube with the sides compressed still cooling. probably wont have a free fermenter for it until the weekend, or maybe early next week so no final volume measurement until then


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## Trent (16/4/07)

Thirsty,
You DO write longer posts than Pat! It looks like we are going to get some definite answers one way or another, with all the people doing experiments and stuff. I am happy to agree it could be me reading stuff wrong, though I am a little doubtful (as I am very anal about measuring my grain, and the amounts of water I add), but happy to be proven wrong. Pat wanted me to add that full time brewer is working in a micro, and I hold his advice very highly, but at the end of the day, it appears that at least a few of us are victims to the disappearing sugars, we just need to work on our final figures rather than anything else, and the rest of it (reading mistake or otherwise) is superfluous. I will be interested in reading hte results as they come in, but will be surprised (based on most peoples experiences) if any of them have the drop in efficiency.
All the best (and I will try not to post too much more here!)
Trent


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## PistolPatch (16/4/07)

You know the funniest thing? I actually started this thread to take a break from writing on AHB. My posts were getting longer and poorer in proportion to the long hours I've been working recently. So I thought I better stop answering questions and just ask a couple of quick ones that I had.

This thread was my first quick question. LOL!

*Back on Topic.* This thread is currently stuck. No one has been able to answer the following question as yet...

_I have done efficiency measurements using two different sets of instruments and calibrations for both volume and gravity and the figures have matched. I repeatedly get about a 10% drop in efficiency during the boil. So do some others. Why?_

*How About A New Poll?*

It looks like it's going to take a while for everyone to throw some figures in this thread so in the meantime, how about we do a new poll to determine how many people are actually having the same problem as Trent, myself and the couple of others (including a microbrewer!)?

Writing such a poll well so as to get the most info possible is not a 5 minute job so if anyone has any ideas on how it should be written then throw them in here. (That's you Thirsty Old Boy )

Here's my huge effort so far - lol

Poll: Does your efficiency drop during the boil?
Yes
No

Obviously a little more thinking is needed  A poll title for a start. Here's a few other things that come to mind...

The first post should also explain that trub losses should be added etc. Paragraph 4 of this post would help put the purpose of the poll in context. A link to this thread would be of value in getting a few more people to throw their figures in here using the template I wrote up the other day. People could also add any theories here. Might as well have one big mess rather than than two  

So, if you think a new poll would be worthwhile please fire away with some suggestions and maybe we can whack one up tomorrow evening.

By the way, once we have all this sorted, I'll put a huge edit into Post #1 here with our conclusions and maybe links to some of the top stuff that you guys have written. This way no other poor bugger will have to go where we have gone!

I must say I don't think I have ever seen a thread with such long posts (besides mine). Amazing!

Spot ya,
Pat


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## Thirsty Boy (17/4/07)

You know what Pat,

I think that besides opening a whole off topic can of worms.. you have probably achieved what you set out to achieve in the first place. You were hoping for an AHB standard for posting efficiency, well, I dont think you are going to get that, people are a bit clingy about sticking to their own method.

BUT. What you have managed to make us all do, is realise that not everyone actually means the same thing when they use the word efficiency.

So, from now on, if I post a recipe. I'll probably just stick to using the "into the kettle" figure that I'm comfortable with. But instead of just saying efficiency, I will try to remember to say Pre-boil Efficiency. Whereas Trent would need to say Total Brewhouse Efficiency.

As long as we all say which type we are quoting, people can do the conversion for themselves. That even takes care of those of you with the mystery efficiency loss.

I know you wanted something easy for newbies to interpret, but bugger it, they can just ask what we mean. At least if we are making it plain that we are talking about different efficiency figures, they know that they HAVE a question to ask.

I think that you have once again done a service to the AHB community here mate. Well done.

Thirsty


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## Trent (17/4/07)

Thirsty Boy
I whole heartedly agree with you. If people wanna post their efficiencies, its probably best to state which kind. Ya shoulda piped up with that 6 pages ago!  Good stuff (simple, but very smart).
All the best
Trent


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## Thirsty Boy (17/4/07)

On the topic of a new poll or whatever. I think you are asking the question in the wrong way. By using the word efficiency, you are confusing the issue. Forget about losing efficiency, you are losing _extract_ (or sugar if you want). Efficiency is all about how much extract you get, as compared to how much it would be possible to get in a perfect setup. There's a whole bunch of factors there that are completely irrelevant to what you are experiencing.

So when your efficiency (no matter which type you mean) drops, it is because you have lost sugar somewhere.

So the question should be - *Do you suffer an unaccountable loss of extract during the boil?*

Then you can stop worring about the possible vagaries of Promash or Beersmith and whether people are entering their losses to deadspace etc. you just calculate extract Gravity x Volume. It doesn't even matter what unit you measure gravity in. SG, Plato, Brix... all effective for the purpose at hand.

If you have less points of extract at the end of the boil than the start... where the hell did they go??

Then make them think about where they might have gone. Tell them to account for...

Trub
Hopbag
Deadspace
Chillers
Samples
Thermal expansion/contraction
Spills/boilovers
Leaks
anything else you can think of

When they have accounted for all that, if there are still missing extract points

Then they have to think about how accurate they are actually able to be in measuring. If they _really_ take into account all their possible areas of uncertainty and their loss is greater than could be accounted for by systemic inaccuracy, then.... well then they have an unaccountable loss.

And they can tick the "yes" box on the poll.


Or something like that anyway

Thirsty


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## bayWeiss (17/4/07)

It is my belief as well that "pre-boil"efficiency should be the only "efficiency" number ever quoted for recipe giving/taking/trading.

"Post-boil" efficiency numbers carry all of the potential error baggage as listed in Thirstyboy's post... and it would be almost impossible to replicate things based on that number.

Even if there were no errors in measuring, there is still the question (does this measurement take into account the break material?) Whereas the only question needed when using "pre-boil" efficiency numbers is of grain potential.

cheers!


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## Ross (17/4/07)

Excellent post as always Thirsty Boy - shame you & Pat aren't neighbours, then maybe some of these threads would gell a bit better & would attract a wider input.
Brewhouse efficiency is all that matters to the brewer (me anyway) putting his recipe together - what you get in your fermenter for the ingredients mashed & volumes used. Personally i couldn't give a damn whether i lose sugars in the boil, if you do, you do. i just want accurate predictabillity/repeatabillity of results & that i have.
I'm looking forward to Thirsty Boys controlled experiment; toyed with doing it myself, but he has the technical resources to give it true credibillity. Personally, as mentioned before, I believe it's down to measuring inaccuracys, if it isn't & we do lose sugar to the wort, i'll have learnt something which is always good.

cheers Ross


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## PistolPatch (17/4/07)

Rossco, that's two long posts in a row - good on ya mate! I reckon it's a shame Thirsty and I aren't neighbours as well. He's just sent me a 3 page PM on another topic we've been mucking around with which is another great read - going to take me a good hour to digest! If we were neighbours we'd spend the whole night talking instead of posting. Perfect!

Thanks very much Thirsty, Trent, Bayweiss and Rossco for your comments today and prior. Before I try and get my head around all the info provided re a new poll, have you any thoughts on the following?...

I mean, it would be great if everyone explained what efficiency figure they were using but they don't. I've suggested this before. In fact, about 6 months ago I pushed that point a few times (purely through ignorance as you will see below) but of course, no one does it. People still say, 'My efficiency was 76%.'

So, how about the following to temporarily, until we get more figures, summarise this thread? (I haven't given any credits or whacked in links to anyone's top posts. We can do this in the airlocked thread that will inevitably result from all this )

Here's the edit I plan to whack at the beginning of Post #1. Any improvements before I add it?

*EDIT: AN ANSWER TO THE THREAD QUESTION (Based on the First Eighty Posts to this Thread)*

The poll shows clearly that currently there is no standard way in which people post their, 'AHB Efficiency.'*

I began this thread because my efficiency into boiler figure is always about 10% higher than my, 'final efficiency.'* I never put much thought into this until now as I when I do measure I am fanatical - I thought at the time of posting, that everyone's 'efficiency,' dropped during the boil. Theoretically though, this shouldn't happen. But, a few people are getting similiar figures to myself including one professional brewer. Other people are finding that their efficiency into boiler and final efficiency do match. Other people don't know as they only take one efficiency measurement per brew.

So, at this stage, the answer as to the best way to post your efficiency on AHB depends on your figures.

**Final Efficiency or AHB Efficiency*

One thing that the overwhelming majority of posters here agree on is that when measuring your, 'Efficiency Into Fermenter,' you should include your losses to trub. So, in other words, if you end up with 23 litres in your fermenter and you have left 2.6 litres in your kettle or in pipes etc, then you should call your final volume 25.6 litres. This figure does not have a name so I will call it your, 'Final Efficiency,' or your, 'AHB Efficiency.'

So...

*If Your Efficiency Into Boiler Figure Equals Your Final Efficiency Figure*

Obviously, if with your measurement regime, these two figures match, then you can post either figure as it will equal your 'AHB Efficiency.' Things are easy for you guys!

*If Your Efficiency Into Boiler Figure is Higher than Your Final Efficiency Figure*

Those of us who are finding their Efficiency Into Boiler figure is considerably higher than their Final Efficiency figure should, when posting publicly, use their final efficiency figure. If we do this then everyone's figures will be in agreement.

*Why Isn't Everyone Getting the Same Figures?*

At this stage we don't know. We have only a few figures to work from so far and so are currently trying to get more brewer's figures. If you are interested in this question or in contributing your efficiency figures then you should read this thread from Post #59  onwards. Post #59 contains a very pedantic template of how to measure your efficiencies. The less pedantic measurers can forget the hop adjustments contained in that post. The figures you come up with will be close enough.

*END OF EDIT. The original post is as follows...*

Is that OK guys? (God knows who will read that much anyway - lol!)

Spot ya,
Pat


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## PistolPatch (22/4/07)

PistolPatch said:


> Is that OK guys? (God knows who will read that much anyway - lol!)



From the total lack of replies, I think I may have the answer to the second part of the question above. I must have put everyone to sleep - lol!

Anyway, no one has said it's wrong so unless I hear anything in the meantime, I will add the edit proposed in the post above with a few small changes later this morning.

I was hoping we'd have some more figures by now  (Anyone brewing today?) To get some more info/figures, I'll probably start that other poll as well later this morning so please chuck your vote in there. Will also incorporate Thirsty Boy's suggestions to the poll with the exception of one thing I'm uncertain on and have just emailed him about. (Thanks mate!)

Spot ya later,
Pat


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## Thirsty Boy (22/4/07)

Its very very sad Pat, both of us are posting when any reasonable human being would be in bed.

Your format for posting efficiency is fine. It means that we are all talking about the same figures no matter what has happened on the way to getting them.

All you have to do now is get people to start using the convention. I suggest that everyone who has been following this thread, make an effort to ask.... if you dont see an explanation of what type of efficiency is being quoted... ask. Eventually people will get into the habbit.

TB


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## MHB (22/4/07)

Just a thought about the "Missing Mass".
I havent sat down and run the numbers through however:-

The hot break material is in solution at the start of the boil, it's on the bottom of the kettle at the end of the boil.

This mass does contribute to the sweet water density.
But it is missing from the wort density.

It might account for some of the change in calculated efficiency.

MHB


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## Hogan (22/4/07)

Hogan said:


> Runnings off the mash Brix *18 (1.075)*
> 
> 1st sparge Brix *9 (1.037)*
> 
> ...





After trying some different figures in BeerSmith I find that to get exactly the same efficiency % pre and post boil can be achieved by increasing my listed post boil volume by only 700 mls. As I cannot guarantee that my volume figure of 24 lts is 100% accurate I cannot say with any degree of certainty that there was a difference in the efficiency figures.

Cheers, Hoges.


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## PistolPatch (22/4/07)

OK, I've chucked the new poll up here and added the edit to Post #1 of this thread. I didn't put Thirsty's points in the first poll of the new thread. I thought it might be wise to keep them in reserve. This reserve has now just been used - lol!

MHB: That'd be great if you could do some calcualtions on it. I suppose the only way for the average home brewer to ensure there is no discrepancy there would be to either take the sample just before the boil ends as I wrote in Post #59 or stir the hell out of it at the end of the chill.

On that last brew though, I think I took the sample just after the end of the boil - maybe a minute or two after. Would a lot of stuff drop put of suspension in those few minutes. I hope so as this could be what is going on. Might do a brew on Wednesday and get some more figures. Need more kegs though!

Spot ya,
Pat

*Hoges:* Just caught your post. Yeah that's only a small difference. Mine needed about a 3 litre change. If I were you, I'd vote that there is no change in your efficiency. Thanks to you, I've just added an instruction that if people have less than 5% change then to consider this as no change. Thanks for this and your figures mate.


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## MHB (22/4/07)

Ref _Kunze; Technology Brewing and Malting_ 
Hot Break is typically about 1.42 Kg/100 L
Cold Break about 0.22 Kg/100 L

Just a quick play with the numbers (I realise that there are some other factors, but I think they are below the resolution of the measuring equipment in use)
Total break material ~1.64 Kg/100L, 
If the sweet wort was say 1.050
You loose from the solution about 1.42g/L on Boiling and another 0.22g/L on Cooling a total of 1.64g/L.
So you loose some apparent density, the true value for the sugar content of the sweet wort should be ~1.04836, rather than 1.050.
0.05-0.04836 = 0.00164
(0.00164 / 0.050) X 100 = 3.28%

About a 3.3% apparent loss in efficiency; caused by break formation.

Break once it forms can't be stirred in and measured; it has come out of solution, it has no more effect on the gravity reading than would a teaspoon of sand in the bottom of your hydrometer tube.
Even if it's stirred into suspension, it won't affect the gravity reading.

MHB


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## Hargie (22/4/07)

....doubt that this will help....




....yesterday i brewed the house Weizen....

....9.38 kg grain....my recipes are always set at 80% efficiency...

....48 ltrs for pre boil of 1.052 = 85% efficiency ( pro-mash)

....39 ltrs "final efficiency" 1.064 = 91% efficiency.....

....minus 3 ltrs kettle/hop/trub losses = 36 ltrs...

....add 10 ltrs dilution to get 46 ltrs @ 1.050 = 83 % efficiency....




.....buggered if i know.....


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## PistolPatch (22/4/07)

*Hargie:* These are just the figures we are after. It looks as though yours are going up during the boil but a few other people have got this too.

It would be great if you could, while it's fresh in your memory, have a look at how the way you took your measurements differed from the guide given here and also consider the things that Thirsty Boy mentioned in his post here

Thanks for taking the time to post. From what I see of the polls so far, everyone's figures are a bit all over the place. The only way we will find out why is if people like yourself take the time to post their figures and then have a good think on the above (or vice-versa if they haven't already done their measurements.) Many thanks to you Hargie and please post here again if you can either find any criticism of the way you measured your own figures or if you are confident in them. Either way will give us valuable info.

*MHB:* Great to see a post like yours. I was actually pretty excited about this until Adamt and I were talking earlier today and he pointed out that the theory actually worked the opposite way to explaining a decrease in gravity during the boil. Agh!!!! Oh well! The info you provided though is certainly valuable. I love posts like that.

:super: 
Pat


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## Thirsty Boy (23/4/07)

> *MHB:* Great to see a post like yours. I was actually pretty excited about this until Adamt and I were talking earlier today and he pointed out that the theory actually worked the opposite way to explaining a decrease in gravity during the boil.



Sorry... hows that? You just gave me a damn headache.

If you precipitate out some dissolved solids from a liquid, the liquid becomes less dense. If you were measuring density in order to determine sugar content and from that efficiency (god I wish we could just use points of extract...) then less density due to protien break formation, would read on your hydrometer as less sugar and therefore a loss in efficiency accross the boil.

But you say the other way?

To quote another confused Australian - - - Please explain.

Thirsty

PS. Am I insane, or has thre been a bit of an error. 1.64kg/100L doesn't equate to 1.64g/L it equates to 16.4g/L MHB, does that mean that everything is out by a factor of 10? or did you mean per 1000L ??

BTW, the loss of protien break wouldn't effect a refractometer reading would it? The refracto is actually reading dissolved sugar, not inferring dissolved sugar from specific gravity


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## PistolPatch (23/4/07)

Ah excellent! You are right Thirsty. It does work in favour of explaining a decrease in efficiency. Shame it's only 3.3%. Adam and I mustn't think too well when sober 

Thanks mate :super:


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## Gulf Brewery (23/4/07)

Hargie said:


> ....9.38 kg grain....my recipes are always set at 80% efficiency...
> ....48 ltrs for pre boil of 1.052 = 85% efficiency ( pro-mash)
> ....39 ltrs "final efficiency" 1.064 = 91% efficiency.....
> ....minus 3 ltrs kettle/hop/trub losses = 36 ltrs...
> ...



Folks

If you use promash correctly, the efficiency includes all of your water additions (dliutions) and losses (sparge, grain absorption). You must have the correct batch size set otherwise you will get these variations. eg - change the amount of water added to kettle and you efficiency doesn't change, your calculated SG doesn't change, but your OG does. This is not the easiest program to use in this area. 

Cheers
Pedro


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## Hargie (23/4/07)

....i always brew full( 2x23 ltr) batches , so i have Batch size set to 46 ltrs and wort size set to 36 ltrs. With my system i boil 48 ltrs down to 36ltrs (39ltrs minus 3ltrs trub/hop crap etc) over 90 mins. Then i add 10 ltrs refridgerated water (helps get pitching temp lower)to fermenters to get 46ltrs. Does this mean i should set Batch size to 36 ltrs..???

...i love Promash and it gives me very reliable results. My recipes are almost always set at 1.050 and 80% efficiency and this what i get.Any variances are usually a slightly higher OG & recorded efficiency...


...i have noticed that my pre boil gravity is a very good indicator of what my OG will be, with the OG being within a point or two either way of the pre boil grav. I think MHB's post may explain that very well for me.






> Ref Kunze; Technology Brewing and Malting
> Hot Break is typically about 1.42 Kg/100 L
> Cold Break about 0.22 Kg/100 L
> 
> ...


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## Tony (23/4/07)

I dont worry about efficiency too much

I just set it at 75% and i usually get around 74 to 78% Higher if i do a decoction.

I have always wondered why i get fluctuations in efficiency.

I just put it down to the crack of the malt and if i stired it enough.

Interesting to see that break has an effect.

I have been adding the irish moss tablet later in hte boil latley and getting great break and very clear beers but lower efficiency.

that explains part of it i guess.

generally if i can get within 1.002 of my target im happy and i usually do.

cheers


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## bugwan (23/4/07)

I'm with Thirsty Boy on the measurements side of things. I went back to the maths books and calculated my kettle graduations using Pi x R squared x depth!! Do you think I could get that to match a graduated container of 5L amounts? Hell no!

My dipstick is worth it's weight in paper..pretty useless but it's an estimate (which suits my current brewing style).

For what it's worth, I note all efficiencies, but the 'into fermenter' is the one most important to me...as it's the one I drink!


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## Gulf Brewery (23/4/07)

Hargie said:


> ....i always brew full( 2x23 ltr) batches , so i have Batch size set to 46 ltrs and wort size set to 36 ltrs. With my system i boil 48 ltrs down to 36ltrs (39ltrs minus 3ltrs trub/hop crap etc) over 90 mins. Then i add 10 ltrs refridgerated water (helps get pitching temp lower)to fermenters to get 46ltrs. Does this mean i should set Batch size to 36 ltrs..???



Hargie

I think your batch size is 36 litres and your promash figures should be based on what you get after the boil and before dilution. 

Cheers
Pedro


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## bayWeiss (24/4/07)

MHB said:


> Ref _Kunze; Technology Brewing and Malting_
> Hot Break is typically about 1.42 Kg/100 L
> Cold Break about 0.22 Kg/100 L
> 
> ...



This makes perfect sense. It is so logical, but somehow the computer in my head did not think about it. LOL. Add this on top of reasonable measurement/equipment error, and it seems like one could easily measure an efficiency with a value of of -5% or so of their pre-boil OG. This is one more reason why I believe only Pre-Boil Efficiencies should be referenced, and not post-boil.


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