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

[TidalPete]

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

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

:beer:

 

[poppa joe]

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

 

[PistolPatch]

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.)

 

[Corny]

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.

 

[bayWeiss]

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!

 

[PistolPatch]

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.

 

[oldbugman]

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?

 

[PistolPatch]

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!

 

[PistolPatch]

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.)

 

[Stuster]

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.

 

[bayWeiss]

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!

 

[NRB]

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.

 

[PistolPatch]

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.

 

[PistolPatch]

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

 

[PistolPatch]

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)

 

[PistolPatch]

[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.

 

[brendanos]

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!

 

[PistolPatch]

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!

 

[bayWeiss]

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!

 

[Stuster]

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).