Measuring Post-boil Efficiency

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QldKev

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I noticed from the video in this thread on the Braumeister about how the post-boil efficiency was measured. It took into account all the waste wort and hot break etc. I've always used the final volume into the fermenter/cube.

I checked the efficiency using the grain bill from the video based on how I measure mine. I think he worked it out as 86% (cant check youtube from here) I work it out as 67% into the fermenter. (I did use Marris Otter as I don't have Perl in BeerSmith)

I got thinking about this maybe I have been doing this incorrectly. So I had a search and from what I understand you measure wort into the fermenter.
http://www.howtobrew.com/section2/chapter12-5.html
http://www.beersmith.com/blog/2008/10/26/b...n-beer-brewing/

What matters for a post boil gravity is the original grain bill, and the gravity/amount of wort collected into the fermenter.


How does everyone else measure the efficiency into the fermenter?


QldKev
 
Thats how I measure mine too kev. I was seeing all these big numbers and thinking that my 65-70% Brewhouse efficiency was shite... Now I realise it was pretty good. I guess what we call it is irrelavent if we know how we are calculating it.
 
I've noticed a lot of people quote mash efficiency figures and label them brewhouse efficiency incorrectly. From my understanding (although the formulae/math is beyond me) you are correct, Kev. However it is calculated, it's the mash efficiency minus the losses on its journey to the fermenter. You could have an average sugar conversion percentage, but a really minimal loss to trub and end up with the same efficiency as someone with an excellent mash efficiency and high losses to trub.
 
As far as I'm concerned brewhouse doesn't tell you anything about the stuff that matters, ie how much extraction you get from your grain. This also affects colour

It's a little like how some people say they try to limit their efficiency to 70% to avoid over sparging, well if you over sparge you can limit your efficiency into fermenter by just wasting some sort, but if you're measuring into boil, end of boil or mash efficiency then your over sparging will be evident

Calculating a recipe on mash efficiency will allow you to hit your OG, then the trick is to simply have enough wort end of boil to account for losses.

As long as you're explicit about which efficiency you mean it's fine

FWIW, I calculate my recipes based on a Conversion Efficiency of 99%. Essentially this means the kettle and lauter losses are irrelevant to me ;)
 
Thats right fellas, A true Brewhouse efficiency is just that, and I guess for a full scale commercial brewery the Brewhouse efficiency is important, its everything. At the end of the day they want to know how many cases of mega swill or whatever they got out the factory door. Losses would also include trub and kettle losses plus the cases that fell off the fork lift or whatever.
For us, or me anyway, I can manage my losses as they neither here nor there. An extra $1 of malt is no big deal for a little extra trub. So I just want to know what efficiency I got after the boil and chill. So I call it brewhouse efficiency but I always follow up by saying "post boil efficiency"
 
I use Brewmate and I think I am correct in saying that they use Brewhouse efficiency which includes boil off rate, MLT dead space, losses in the kettle to trub etc, and the 4% loss when the wort is cooled. Its is the amount of wort into the fermenter, all the losses and the grain bill, which is used for the final calculation. I have Brewmate set to 67% efficiency, if I do a mash efficieny calculation, it is around the 90% mark.
 
Pre-boil efficiency I think is pretty straight forward.
It's the total volume in the kettle, which is basically after mash tun losses etc, but includes any kettle losses.

But it is the post boil terminology that is throwing the calculations,
to me
Mash post boil efficiency that includes all the trub etc
Brew house post boil efficiency, that only includes what hits the fermenter.

Personally I always allow a couple extra liters in the batch at the kettle stage, so I don't need to suck down every last ml and risk too much break material ending up in the fermentor/cube. As SJW said, it's only a couple of dollars extra. But although my mash efficiency is good, allowing that wastage does mean my brewhouse efficiency is reduced, but I'm more concerned about making a decent beer than making decent numbers.

I don't think one number is necessarily a better number to use over the other, I think really the issue is when comparing numbers we need to know if all the trub etc has been measured, as this results in two very different numbers.

QldKev


edit: thinking about it, the mash post boil, should equal the pre-boil efficiency or be pretty close
 
The way I see it the only ones that are relevant especially if your talking about a recipe being brewed by other brewers is the pre boil efficiency and to a lesser degree the post boil efficiency before transfer to fermenter, these are the ones that will be most accurate over most systems particularly the pre boil one.
Brew house efficiency, or efficiency into fermenter is totally irrelevant when brewing on different systems as each system will have it's own differing losses after the boil.
 
I think the problem comes when actually using the Losses to Trub and Chiller (in Brewmate anyway, other software could call it something else) to try and account for those losses. I just tried increasing my Losses to Trub and Chiller to 100L to make it obvious, the only values that changed were the required sparge water, and pre-boil and post boil volumes, not the gravities. This means that Brewmate assumes there are no sugars in your trub losses, only water.

That's why I set my trub losses to 0 as far as the software is concerned, and just allow for it in my final volume

Try it yourself, by changing my trub losses to 100L Brewmate predicted I should get 144L of 1.040 wort preboil, from 4.6kg of grain. Beat that for conversion efficiency... ;)
 
I think the problem comes when actually using the Losses to Trub and Chiller (in Brewmate anyway, other software could call it something else) to try and account for those losses. I just tried increasing my Losses to Trub and Chiller to 100L to make it obvious, the only values that changed were the required sparge water, and pre-boil and post boil volumes, not the gravities. This means that Brewmate assumes there are no sugars in your trub losses, only water.

That's why I set my trub losses to 0 as far as the software is concerned, and just allow for it in my final volume

Try it yourself, by changing my trub losses to 100L Brewmate predicted I should get 144L of 1.040 wort preboil, from 4.6kg of grain. Beat that for conversion efficiency... ;)

To me that sounds more like an update is needed in Brewmate,

I wonder if BeerSmith does the same, can't check from here.

QldKev
 
The more I read about how people use programs the more I find they all calculate things differently. That is why I like recipes that give final volumes and gravity with a grain bill in percents and the IBU goal. If you tell me you made 20 liters of 1.045 wort at 35 IBU with a grain bill and hop schedule I can use my program to make it work on my system. Weather you got 50% or 90% efficiency makes no difference to how I brew.

Efficiency is only relevant if it is calculated the same. For our small scale brewing it is only a way to tell how you do compared to others. Way too much sleep is lost over efficiency.

Calculating is not hard. Not sure what the correct formula is for metric. I have not calculated efficiency by hand for so long I could not tell you how to do it for gallons.

One interesting bit I learned when working out the calculations I use in a modified version of SUDS excel sheets is hops can suck up sugar. Not the kind of hop usage for most beer, the kind of hops for crazy American IPAs. It is not a big number, however I have a way to calculate how much wort is lost in the hops left in the kettle. When I brew a crazy IPA for the wife my final volume is now correct and not short.
 
I just measure the efficiency of how much beer I get to bottle and keg: bottom line amount of beer to drink, that's what matters to me.

(20L BM: 75-77% based on 21.5L to actually drink)
 
I just measure the efficiency of how much beer I get to bottle and keg: bottom line amount of beer to drink, that's what matters to me.

(20L BM: 75-77% based on 21.5L to actually drink)

That'd be the Efficiency Into Packaging ;)
 
You see I dont care about my true brewhouse efficiency as I stop running off into the fermenter once I get 20 litres in there. So often there is quit a bit left in the kettle that I could ferment and bottle but I dont want to bottle any. I just want enough for a cornie keg. So true brewhouse efficiency means nothing to me.
 
You see I dont care about my true brewhouse efficiency as I stop running off into the fermenter once I get 20 litres in there. So often there is quit a bit left in the kettle that I could ferment and bottle but I dont want to bottle any. I just want enough for a cornie keg. So true brewhouse efficiency means nothing to me.

Yep, I turn the rest into frozen starters
 
mash efficiency = efficiency into the kettle
brewhouse efficiency = efficiency into the fermenter

adding trub to your brewhouse efficiency isnt really doing anything but pumping your numbers up.
doesnt make sense to me to add the trub to your efficiency, its not efficient at all if its going on your lawn and not into your fermenter..


either way i guess it doesnt matter what way you measure it yourself aslong as its consistant, it just doesnt mean anything at all when you try to compare it with others unless they are doing it the same way
 
Its been a bugbear of mine for years, to keep the two apart I use two terms Brewhouse Efficiency and Brewhouse Yield the reason we need to account for the kettle loss is that what you lose contains the same amount of extract and is bittered to the same extent as the rest of the wort.
Lets say two brewers make exactly the same beer and that at the end of the boil they both have 27L in the kettle at a gravity of 1.040, one knocks out 25 L and looses 2L the other knocks out 22 and looses 5 L.
As the wort is 10% extract the end of boil worts contain 2.7 Kg of extract, one brewer is getting 2.5 Kg of that into the fermenter the other is getting 2.2 Kg thats a difference of 18% in the brewhouse yield. Even tho both brewers made the same amount of the same wort and both achieved the same Brewhouse Efficiency.
When it comes to recipe design its much easier to look at the total amount of wort at end of boil and let the brewer decide how they divide that between knockout and loss, a canny brewer will from time to time look at their whole brewery process and can see quite easily where their losses are and where they can make improvements in yield even tho they are still making the same amount of wort.
Mark

As an aside, I just look at my Brewhouse yield, I have my losses where I want them and my beer is at the point where getting more means lowering the quality, my brewhouse yield is around 70-72% for most beers and Im happy with that.
M
 
i dunno, its like working out the fuel efficiency of an engine by including the heat and wear into the efficiency of actually moving the car forward
as theres always some waste i thought thats what the efficiency numbers were used for, accounting and compensating for the losses in the end product

i guess thats the thing with homebrewing though, aslong as your consistant with your measurements it gives you a base to work from, it just makes it hard for comparison

i thought the efficiency quoted on recipe's was efficiency into fermenter?

not trying to sound facetious or anything, efficiency is always something ive been interested in for the reasons stated in this thread
 
I work of 50%
My piece of string may be diiferent from yours
 
I use beertools, all I do is set my efficiency to 84% then it adjusts the weight of grain needed from the original recipe. I know from a 50L batch i'll need to make 55L so thats what I set as my final post boil volume. I sparge with 20L to make my preboil volume and gravity is always on the money. At the end I'll save 2L for a starter or have 52L in fermentor and dump the other 3L of trub.

I don't understand the part about efficiency into fermentor? i'll have to have another read. I really couldn't care less if my efficiency was lower all I really care about is my preboil and post boil specific gravitys and what to set my efficiency at to know how much weight of grain to use to achieve this.
Cheers
 
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