Efficiency ?

[Hashie]

Hi all, hoping to clear up some efficiency issues.

I've just finished a pale ale, recipe as follows;

Powell's Pilsner 2.4 kg
Powell's Munich 0.80 kg
Wheat malt 0.80 kg
Caramalt 0.25 kg
Carared 0.10 kg

Amarillo 20g 60 min.
Amarillo 15g 10
Amarillo 9g 5
Cascade 6g 5
Cascade 15g 1

15 minute protein rest @ 55 Deg.
60 minute mash @64
Mashout @77

90 minute boil

BIAB 35 litre starting volume

Efficiency into the boiler was 84.6% @ 8.2 Brix (1034 SG) with a volume of 33.5 litres.
Efficiency post boil (this is were it gets funky) 72.42% @9.4 Brix or 1039 SG with a final volume of 25.5 litres.

It makes no sense to me that I can have great efficiency into the boiler, yet lousy into the fermenter.

Any thoughts?

 

[matti]

Promash calculates post boil of brix 11.3 1.049.

You have mucked up somewhere in measuring the brix.
Did you calibrate the refractometer?
Did you cool down sample prior to reading it?

Matti

 

[Hashie]

Yes I did calibrate a couple of months ago and the sample was cooled to room-ish temp before reading (currently 30 Deg.)

The wort is in a no-chill cube so I might take a hydro reading and another refrac tomorrow to see if there is a discrepancy somewhere.

 

[enoch]

Or your volume readings are off. A few litres in measurement error at either end would muck up your efficiency calc's.

That is a fair amount of shrinkage between 33.5 into the boiler and 25.5 into the fermenter.

 

[Adamt]

Just about all calculations people make for "efficiency into kettle" are wrong. The reason being the temperature dependent density of water/wort; many people do their SG readings at 20C which is correct, but the volume in your pot at mash out/boil temperatures must also be referenced back to room temperature for direct comparison.

 

[Hashie]

Ok, re-took some readings this morning. Very different to yesterday.

Today I got 9.8 Brix at room temp, or 1041 SG = 76.14% efficiency (good enough) This was after adjusting final volume by -4% to account for expansion @100 Deg.

Still doesn't account for yesterdays reading but I guess I'll just have to continue on until I can get a standard reading.

 

[afromaiko]

What should we be most concerned about, into the kettle or into the fermenter? Which one do people around here usually quote when they talk about their efficiency?

 

[MHB]

This got done to death about a year ago.

There is a tendency for people to quote the biggest number they can find so we often hear Mash Efficiency quoted. Although mash efficiency is a very useful tool for managing and improving your processes and yield, Brew House Efficiency is the one that really matters.

If you know your brewhouse efficiency you can at least workout how much grist you need for any brew of a given volume and density.

I think it would be helpful if people specified which they were referring to, when it isnt obvious by context.

MHB

 

[Thirsty Boy]

What should we be most concerned about, into the kettle or into the fermenter? Which one do people around here usually quote when they talk about their efficiency?

Many a merry argument had about this one - my take on it is this. Mash efficiency (or efficiency into the kettle) is the simplest number to use - If you are communicating your recipe to another brewer.

For your own purposes, inside your brewery - its probably brewhouse efficiency (or efficiency into the fermentor) that counts the most

Either way, if you don't know which figure someone is using, then the number they quote is virtually meaningless.

I vote we all forget about efficiency completely and just quote recipes using %of grist weight and a fermentor SG

my Vienna lager is

75.5% Pilsner
10% JWM light munich
10% JWM Crystal
2.5% JWM Light Crystal
2.5% Wey Melanoidin

with a an OG of 1.048

see... no need for an efficiency figure at all, nor a batch size

BUT... if you choose to use efficiency, just say which one you mean and then we can all work out what it means to us.

TB

 

[matti]

This got done to death about a year ago.

There is a tendency for people to quote the biggest number they can find so we often hear Mash Efficiency quoted. Although mash efficiency is a very useful tool for managing and improving your processes and yield, Brew House Efficiency is the one that really matters.

If you know your brewhouse efficiency you can at least workout how much grist you need for any brew of a given volume and density.

I think it would be helpful if people specified which they were referring to, when it isnt obvious by context.

MHB

I couldn't agree more.

Though if you are in the process of attempting to limit your losses it is vital to know where it goes.
So mash efficiency is still very important but should not be bragged about

 

[PJO]

If you know your brewhouse efficiency you can at least workout how much grist you need for any brew of a given volume and density.

I think it would be helpful if people specified which they were referring to, when it isnt obvious by context.

MHB

I have two points to make on this:

Efficiency into the kettle tells you alot about your mashing and extraction, and especially for newer brewers I think that kind of information helps. Adding another variable into the mix by using brewhouse efficiency just makes it a little more difficult.

Also, my brewhouse effeciency changes quite a bit per brew, mainly depending on how much I lose in the kettle due to large hop additions. I don't typically make the same beer from one batch to next, so while my kettle efficiency varies by ~1% per brew (if I don't muck around with my grain mill), my brewhouse efficiency varies quite a bit more.

Cheers
Petr

 

[buttersd70]

I vote we all forget about efficiency completely and just quote recipes using %of grist weight and a fermentor SG

Funny you should say that, TB. Thats exactly how I think of my recipes, and is also how I communicate them to others. I think of everyting in terms of percentages and ratios, hopping included, because that can be translated so easily for efficiency, batch size and also method used (eg concentrated boil or split boil due to size limitations).

 

[Screwtop]

Just about all calculations people make for "efficiency into kettle" are wrong. The reason being the temperature dependent density of water/wort; many people do their SG readings at 20C which is correct, but the volume in your pot at mash out/boil temperatures must also be referenced back to room temperature for direct comparison.

+1 have found that if you work back from the volume you measured in the kettle pre boil and reduce that by about 4% for cooling your brewhouse eff should improve. I used to have the same prob in Beersmith until I started reducing measured pre-boil volume to allow for temp.

Screwy