Experiment returned confusing results

[jmo88]

I think the term efficiency is what's getting people stuck. In your example, based on the definition of "efficient" your brewer A was far more efficient with resources. But brewhouse efficiency isn't concerned with that. The only item BHE is interested in measuring is how effective you were at getting the sugars out of the grain and into your usable wort. Maybe BHE should be brew house EFFECTIVENESS instead of efficiency.

That's right. You can't have a terribly dilute lauter which gives you poor efficiency and claim to be an efficient brewer by boiling longer. Boiling doesn't deserve to be in the BHE equation. You can't be an efficient boiler – it doesn't make sense. Boiling efficiency doesn't really exist.

 

[SpanishCastleAle]

The word 'efficiency' in the context we are using it doesn't necessarily mean 'efficient', it means 'innefficient' just as much as it means 'efficient'. 10% BHE isn't 'efficient' by any stretch but it's still called 'efficiency'.

 

[cimirie]

That's right. You can't have a terribly dilute lauter which gives you poor efficiency and claim to be an efficient brewer by boiling longer. Boiling doesn't deserve to be in the BHE equation. You can't be an efficient boiler – it doesn't make sense. Boiling efficiency doesn't really exist.

By the same token, boiling is the equalizer. You have to have it in the equation. If you're trying to measure how well you pulled sugar out of the grain, it's not accurate to include only your pre-boil.

Efficiency deals with total sugar extracted, not sugar extracted by volume. If you used 100 gallons to sparge 10 lbs of grain, but pulled 95% of the sugars out, that was very effective (which is all BHE is concerned with) without being academically "efficient."

The reason you need to use post boil numbers is that the formula compares your actual numbers to a theoretical yield, which is based on a particular batch size. You need to have a comparable batch to determine %sugar yield which is BHE.

 

[jmo88]

By the same token, boiling is the equalizer. You have to have it in the equation. If you're trying to measure how well you pulled sugar out of the grain, it's not accurate to include only your pre-boil.

Efficiency deals with total sugar extracted, not sugar extracted by volume. If you used 100 gallons to sparge 10 lbs of grain, but pulled 95% of the sugars out, that was very effective (which is all BHE is concerned with) without being academically "efficient."

The reason you need to use post boil numbers is that the formula compares your actual numbers to a theoretical yield, which is based on a particular batch size. You need to have a comparable batch to determine %sugar yield which is BHE.

Well, this is the dichotomy. There are obviously two sides to it, and those on each side find faults in the other. Of course, those that see BHE = lauter eff+ mash eff are not ignoring the effect of boil and transfer on the OG. But, as soon as you try to include boiling and transfer to the fermenter into the equation, I feel that you ignore the importance of lauter efficiency.

Just in case you haven't read some of the concepts regarding the above equation. Check out this page

 

[BigB]

For what its worth, to me it appears that you guys actually agree but are defining two separate measures of efficiency. If it matters, my reference to efficiency regarding the wort was a reference to potential yield vs actual yield, pre-boil. I measure efficiency the way Palmer Does: ((potential yield per pound x # of pounds)/volume collected)/OG pre-boil. At that point I can tell if I'm going to hit my post-boil OG or not and will sometimes adjust accordingly. I'm personally not concerned with my efficiency post-boil because the only thing I could change would be how long I boil(EDIT: I suppose I could change the flame to change how vigorously it boils-but again, that is not important to me personally). There is certainly nothing wrong with looking at the entire process though.

 

[cimirie]

jmo88-

Awesome link. The article is a great source for information. I've seen things like that before, but nothing so in depth. Thanks.

One quote from it that sums up what I'm trying to say much better than I've been able to say myself:

"it is obvious that each additional sparge step (run-off) will bring more of the extract from the mash into the boil kettle and thus increase the efficiency."

It goes on to talk about diminishing returns of additional sparges. Thanks for the discussion this afternoon and the insight! It's appreciated.

 

[cimirie]

For what its worth, to me it appears that you guys actually agree but are defining two separate measures of efficiency. If it matters, my reference to efficiency regarding the wort was a reference to potential yield vs actual yield, pre-boil. I measure efficiency the way Palmer Does: ((potential yield per pound x # of pounds)/volume collected)/OG pre-boil. At that point I can tell if I'm going to hit my post-boil OG or not and will sometimes adjust accordingly. I'm personally not concerned with my efficiency post-boil because the only thing I could change would be how long I boil(EDIT: I suppose I could change the flame to change how vigorously it boils-but again, that is not important to me personally). There is certainly nothing wrong with looking at the entire process though.

I guess the way Palmer defines efficiency is more useful while in-process because as you say, it may allow you to make changes on the fly. I've always used efficiency as a way to measure my performance at the end of the day, not as a tool in-process. Something to think about.