dparsons
07-24-2006, 02:23 AM
I came across this idea on this site somewhere, but couldn't find it again to credit the individual who inspired me. From what I gather, not everybody practices it. I decided to put this out for feedback to see what merit the idea had and if there were any drawbacks.
Basically the idea is to do multiple aerations of a starter instead of just one and get more yeast from the same size starter. The yeast life cycle goes through stages. Given enough food, the yeast go through a growth phase until they run out of oxygen and then start fermenting. Instead of letting them ferment, shake the starter bottle at repeated intervals (every hour or two, depending) to aerate them so they continue the growth phase. This way food becomes the limiting factor for growth and not oxygen. There is some requirement for jar volume verses starter volume to have enough oxygen. I don't know what that is.
I tried this on my latest batch. I used a 1 gallon jar with a 1 quart wort. While not statistically valid, this batch did kick off faster than normal and that with a yeast that is supposed to be a slow starter (Wyeast 3944 Belgian Witbier).
Basically the idea is to do multiple aerations of a starter instead of just one and get more yeast from the same size starter. The yeast life cycle goes through stages. Given enough food, the yeast go through a growth phase until they run out of oxygen and then start fermenting. Instead of letting them ferment, shake the starter bottle at repeated intervals (every hour or two, depending) to aerate them so they continue the growth phase. This way food becomes the limiting factor for growth and not oxygen. There is some requirement for jar volume verses starter volume to have enough oxygen. I don't know what that is.
I tried this on my latest batch. I used a 1 gallon jar with a 1 quart wort. While not statistically valid, this batch did kick off faster than normal and that with a yeast that is supposed to be a slow starter (Wyeast 3944 Belgian Witbier).