could you get an off flavor due to pitching an asston of yeast for such a small amount of wort?
No, I didn't use a full vial. I keep a frozen yeast bank, and I did 1 cup starters for these.
you keep a yeast bank of cheap dried yeast? What's the chances that you're "yeast bank" in contaminated?
Not to nitpick but this should have been done with "fresh" from the pack yeast not something that could have mutated
It's more a matter of natural selection than mutation. In any event, I'm not that worried--none of the yeast I pitched was more than 2 generations removed from the vial
So today I brewed up a light and boring beer so that I could see the effects that different yeasts have on beer. I bought 5 different dry yeasts then brewed up this beer...
Unless you consider vials from White Labs "cheap dried yeast," then no, I don't. I keep a yeast bank of relatively expensive, liquid yeast (and a few that I've cultured from bottles).
So what one was it?
You just quoted two different people, who followed two different processes.
So, the answer is "both".
I have gone as far as 6 generations with no issues (just make big starters and refresh out of that)I'm not that worried--none of the yeast I pitched was more than 2 generations removed from the vial, and the California and English actually were fresh.
Yeah, it doesn't seem like 2 generations would create any problems, I have some whitbread at 3rd generation now with no weird off-flavors.
(I apologize in advance for the population genetics lecture!!!) I haven't read much about mutations in yeast strains on this forum, but natural selection is HIGHLY unlikely the be the culprit. NS actually has little or nothing to do with evolution, really.
Neutral Theory (which is now generally accepted) will give some insight to what could possible be happening, but not likely as it's only been 2 generations. As Neutral Theory states, almost all genetic variability is caused by random mutation and genetic drift, meaning it is actually kind of likely that a random mutated allele could have spread throughout the population (by random genetic drift and chance, not NS) and created slight off-flavors.
berkely.edu said:Evolution 101: Neutral Theory
The neutral theory is easily misinterpreted. It does NOT suggest:
The data supporting and refuting the neutral theory are complicated. Figuring out how widely the neutral theory applies is still the topic of much research.
- That organisms are not adapted to their environments
- That all morphological variation is neutral
- That ALL genetic variation is neutral
- That natural selection is unimportant in shaping genomes
MSAstoria said:It's more a matter of natural selection than mutation.