Sound practice. And this is really, I guess, just an explanation of the mechanism of behavior we already observed. Also it underscores the need to store yeast in its own beer and not rinse, I think. It shows how yeast are adapted to expect a repeated cycle of feeding on the same nutrient medium, even if they don't know what the interval will be. Disruption of that cycle by introducing them into an unanticipated environment is something they can't sustain, I gather. Once they think they're at the start of the cycle, they're committed, and have no plan B.
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In discussing this an important distinction needs to be made between the domesticated strains of yeast we use in brewing and wild-type strains.
Robert makes the point that "yeast are adapted
to a repeated cycle of feeding on the same nutrient even if they don't know what that interval will be."
That is due to brewers' rigorous artificial selection of those strains that offer the best results under a regimen of "a repeated cycle of feeding on the same nutrient even if they don't know what that interval will be."
Wild yeast don't get that luxury. They must be able to survive under unstable conditions.
It's an axiom of evolution, that portions of the genetic code that are unused, frequently become degraded over time. And DNA begets RNA during translation into proteins and enzymes. With organisms like yeast that can reproduce exponentially under ideal conditions, that impairment may happen more quickly as compared to organisms like mammals that have slower reproduction.
Brewers have selected strains that do very well under the conditions we impose on them, but are genetic "weaklings" in combating the varied conditions that wild yeast face.
Compared to the total cost of brewing including both the other ingredients and my time, my choice is to always buy new yeast.