cladinshadows
Well-Known Member
I just finished brewing two small batches (my second and third AG) and I took some conflicting efficiency/gravity readings. Hopefully someone can help me come to the "duh" moment... I feel like I'm missing something obvious, but I'm too stupid to figure it out.
For both batches I used a single-infusion mash for 90 min. at 152F with 1.25 qt/lb of grain, then batch sparged at 170F with 2.5 lb/qt.
For the first batch, I expected to collect about 4 gallons of 1.034 wort, assuming 70% efficiency. I conducted the mash, everything seemed to be going well, hit my temps, etc. Once everything was ready to begin the boil, I took my volume and gravity measurements... I had 4 gallons of 1.040 (took my reading at 154F, measured 1.020), meaning I hit 80% efficiency. Alright! Off to a good start!
Or not. After I finished my boil, cooled the wort with my brand new IC, got it into my carboy, took my reading... I had collected 2.75 gallons of 1.045 at 70F, meaning efficiency of 64%. What gives!? Where did I lose it?
Next batch I performed the same mash, hit all my temps, everything looked good again. This time, I assumed that one or more of the following things may have happened to my last batch:
1) Didn't mix my sparge water and wort very well, so my first reading was not indicative of the actual boil volume once mixed,
2) The temperature of my reading was high enough to introduce some serious error when calculating the gravity.
3) I had too much of my last batch in me and reading the hydro was just too much to ask.
So this time, I took 7 readings (I wasn't worried, just concerned) at various temperatures, mixed everything reasonably well, and double checked a few with SWMBO. The lowest reading I got was that I had collected 4.25 gallons of 1.036, meaning 78% efficiency. OK...
Sure enough, like the time before, I collected a final volume of a little less than 3 gallons of 1.044 wort. That means my efficiency was more like 65%.
So HBT, where did I go wrong?
I can post the recipes if that will help, I just figured this post was long enough already.
For both batches I used a single-infusion mash for 90 min. at 152F with 1.25 qt/lb of grain, then batch sparged at 170F with 2.5 lb/qt.
For the first batch, I expected to collect about 4 gallons of 1.034 wort, assuming 70% efficiency. I conducted the mash, everything seemed to be going well, hit my temps, etc. Once everything was ready to begin the boil, I took my volume and gravity measurements... I had 4 gallons of 1.040 (took my reading at 154F, measured 1.020), meaning I hit 80% efficiency. Alright! Off to a good start!
Or not. After I finished my boil, cooled the wort with my brand new IC, got it into my carboy, took my reading... I had collected 2.75 gallons of 1.045 at 70F, meaning efficiency of 64%. What gives!? Where did I lose it?
Next batch I performed the same mash, hit all my temps, everything looked good again. This time, I assumed that one or more of the following things may have happened to my last batch:
1) Didn't mix my sparge water and wort very well, so my first reading was not indicative of the actual boil volume once mixed,
2) The temperature of my reading was high enough to introduce some serious error when calculating the gravity.
3) I had too much of my last batch in me and reading the hydro was just too much to ask.
So this time, I took 7 readings (I wasn't worried, just concerned) at various temperatures, mixed everything reasonably well, and double checked a few with SWMBO. The lowest reading I got was that I had collected 4.25 gallons of 1.036, meaning 78% efficiency. OK...
Sure enough, like the time before, I collected a final volume of a little less than 3 gallons of 1.044 wort. That means my efficiency was more like 65%.
So HBT, where did I go wrong?
I can post the recipes if that will help, I just figured this post was long enough already.