I just took my first go at washing yeast right after bottling an IPA. And it went exactly as expected. Now I have 3 mason jars in my fridge with about 50 ml of compacted yeast at the bottom and clear water/wort at the top! Yeast: WY1056 Previous Beer: Two Hearted Clone (IPA) When I brewed the TH clone I had pitched the yeast too warm - I didn't take multiple temp readings and I must of hit a major cold spot (read 64) in my kettle because once I got the my temp prob stuck to the side of the carboy in my fermentation chamber it was reading 75!! I cooled it quickly to 64 where it stayed for 5 days and then I let it warm slowly. With all that said this beer ended up with more ester production than I wanted (not too bad though). Here is my question. I am wondering does any negative effects of the yeast carry over in subsequent generations? Obviously, infections can but what about if they were stressed or fermented too hot, create a bunch of off flavors - could this have an affect on the yeasts health and flavor profile they produce in future beers? I assume they essentially "restart" when washed and then given a new "home" but I've learned not to assume in this hobby. I am not particularly worried about this batch (since 75 degrees isn't harmful to the yeast) I am just generally curious now, as I continue to wash my yeast. Cheers!
Yeast do change from batch to batch, they reproduce and replicate so there is variation. I would guess that fermenting at a higher temp causes them to multiply slightly differently and would be a different variation than at a normal temp. I don't know all the technical details behind it. Nor if it would be a bad thing but just different?
For one batch, I would not worry too much about mutations leading to off flavors. I suspect if you start with fresh 1056 and and ferment at 75 and repitch a lot (>10 times) then you might end up with a yeast cake that was prone to throw off flavors. For your situation, I would not worry about it. The initial batch might not be what you were looking for, but the next batch should be fine.
Thanks! I had been pitching on the warm side in my first few batches because the kit instructions just said the kettle should be "cool to the touch"... with that not so helpful advice I generally got substantial esters and fusel alcohol off flavors. I am really sensitive to that now and want to make sure my yeast is happy and my temps are good. So I didn't want my little guys starting off on the wrong foot (since I have at least 3 batches worth now) especially since I plan to use them for a few more generations if I can.
From what I understand the yeast will change based on the wort concentrations and conditions, it is hard to say exactly what those changes will be which is part of the fun of it. I suspect on 1056 it will be difficult to pick out the differences in the next generation batch since it is fairly neutral, I think the differences are more pronounced on more condition sensitive yeasts that create higher amounts of esters/other. I have never done additional with this strain so I could be completely wrong, someone else may correct me. I would bet that if you have your first generation and you get to a 3rd-4th generation to compare against you would start to notice the difference. The other thing that you can do is overbuild a starter on your next batch by about 500mL and collect that to capture that generation, it's easier than washing and a lot less time. The disadvantage is that you start to lose the "brewery strain" that you are creating with the other washing. But, it does allow you to have some of the last batch generation on hand.
Thanks for the info. Yep, I will try to harvest from a large starter soon. I also want to play around with harvesting from bottle conditioned commercial beers, just for the fun of it. Basically, I am very interested in the geekiness and the money saving aspect of all this yeast culturing business. If I cut out frequent yeast purchases I can cut down the cost of a batch by 15- 20% or so depending on size.
Dirty dirty yeast, needs a bath! Oh the joys of yeast washing.. Can't wait to get fully set up again...
My current MO is to collect the yeast (and trub) from the bottom of the fermenter and refrigerate it directly. I then wash, etc., when it's time to wake it up to make another starter or just pitch it. I also just pitched the whole thing (it was pretty clean) to ferment a kvass with good results. In that case, I had harvested it about two weeks prior.
