From @denny:
“The purpose if aeration is that the O2 is used by the yeast to synthesize sterols. Those keep the cell walls flexible to encourage budding.”
From another guy:
“The oxidative growth technique used to produce dried yeasts actually helps to stabilize the cells against the dehydration process, in part by increasing the production of these compounds (by up to 5 times).”
From Lallemand:
“The yeast contains an adequate reservoir of carbohydrates and unsaturated fatty acids to achieve active growth. It is unnecessary to aerate wort upon first use.”
Source:
And this is just one source of hundreds of others I’m sure.
