Yeast Pitching Rates, an experiment

Experimental Brew DayI am not a scientist, but have used test and measurement to good effect in my career. After reviewing my APAV2 notes, it appears that I under pitched by a significant factor. I intentionally pitched at the same rate as the previous brew to eliminate variables other than brewing liquor, however, it stalled and took a bit of teasing to rouse and finish fermentation. It finished very high. So, I really took a hard look at the online pitching calculators, as well as the instructions from Wyeast, White Labs and Fermentis, and frankly, what the heck I was thinking pitching so low in the first place!

I prefer dry yeast, because of the convenience and costs, however I am familiar with building starters up from single vials to the proper pitching counts. I don’t want to mislead you. There is something mentally difficult for me to pay for 4-5 vials of liquid yeast to pitch, so starters are required, and for a 10 gallon batch, I have to usually make 2-3 steps. Yuck. I plan ahead, brewing a starter just requires more advanced planning – and a long trip to the LHBS.

Proposed is that a Belgian Dubbel with a very simple grain bill, and just high enough to skew out of the “1 sachet of dry yeast per 5 gallons of 1.040 gravity beer” realm to help me wiggle out some objective data out of subjective observation. I want to see EXACTLY what happens when you closely follow recommended pitching rates, intentionally under pitch and intentionally massively over pitch. I split a 3 gallon BIAB batch into individual fermenters, and VERY carefully weighed out the dry yeast into the appropriate gram weights. I rehydrated at 10X the weight and pitched warmish – at 86F. I am fermenting warm in general in the low 70s to add more stress.

I am already seeing results, all three batches are showing activity in less than 2 hours, with the over pitch showing significant krausen! Turns out that if you follow instructions, good things happen, at least with yeast.

My hope is that in about a month and half, I can pull together a few people to do blind tasting, and get some empirical information about pitching rates. Ok empirical only about this batch under these conditions on this yeast… but still… good data.