Efficency calculation correct ?

[chillhuman]

I brewed a batch of beer today, which was 9#4oz British 2row and 12oz 120L crystal malt. I ended up w/ an OG of 1.060. When I did some quick calculations, it looks to me like there is a possible total of 35.5 gallon points theoretical max, where as I ended up with 33 gallon points. This would be an efficiency of over 90%, which I tend to believe is NOT what I'm getting. I set the crush on my barley crusher 1/4 turn tighter, which made for a much finer crush, but the sparge took too long for what I want to spend on a batch. In any case, is my math correct here?

 

[Bobby_M]

The one piece of the equation you left out is the volume of the liquid in which you took this sample from. Was it post sparge or post boil?

 

[chillhuman]

Post boil. Went from 6.5 gal -> 5.5 gal over 90min

 

[explosivebeer]

I brewed a batch of beer today, which was 9#4oz British 2row and 12oz 120L crystal malt. I ended up w/ an OG of 1.060. When I did some quick calculations, it looks to me like there is a possible total of 35.5 gallon points theoretical max, where as I ended up with 33 gallon points. This would be an efficiency of over 90%, which I tend to believe is NOT what I'm getting. I set the crush on my barley crusher 1/4 turn tighter, which made for a much finer crush, but the sparge took too long for what I want to spend on a batch. In any case, is my math correct here?

Here are my calculations (which may or may not be right):

Max Extraction
9.25 lbs 2-row (max ppg 38) = 351.5
.75 lbs 120l crystal (max ppg 33) = 24.75

351.5 / 5.5 = 63.91
24.75 / 5.5 = 4.5
Total = 68.41 ppg

Your Extraction (volume * gravity)
1.060 at 5.5 --> 60

Your Efficiency
60 / 68.41 = 87.7%

 

[Bobby_M]

BTP is giving me 91.48% with an assumption that the English 2-row is MO at 36ppg.

 

[chillhuman]

Here are my calculations (which may or may not be right):

Max Extraction
9.25 lbs 2-row (max ppg 38) = 351.5
.75 lbs 120l crystal (max ppg 33) = 24.75

351.5 / 5.5 = 63.91
24.75 / 5.5 = 4.5
Total = 68.41 ppg

Your Extraction (volume * gravity)
1.060 at 5.5 --> 60

Your Efficiency
60 / 68.41 = 87.7%

That's about what I got too. I think I used slightly different theoretical max values, which is why I was showing 91%. That's awesome then. It was a long wait for the sparge, but hitting upwards of 85% in eff. is great! Thanks for the numbers. Having another calculation to double check against really helps.