When yeast harvesting goes sideways

[shacked]

I've never harvested yeast before so I thought today would be as good a day as any to give it a go.

I brewed an AG american wheat based on brewing classic style's apricot wheat beer. Instead of apricot, I am using cherries. The recipe called for racking onto the cherries 'when primary fermentation has slowed'. I was 2 points off my target gravity, so I racked onto my pasteurized cherries (cheers to Manticle for the guidance on the cherries).

Being a tight ass I thought I'd reuse the WLP320 yeast so I poured 1L of boiled and cooled water onto the yeast cake, gave it a swirl and filled a small kilner jar with yeast, trub, beer etc.. Left the jar in the fermenter fridge to settle while I cleaned up the rest of my gear.

I came back 20 mins later to find the jar overflowing with foam all over the fridge. Yes.. I now realise that 'a few points of FG' = 'still containing fermentible sugar'. Thanks to wollies for the crap, non-air tight jars; otherwise I'd be in trouble.

I quickly sterilised 2 pyrex flasks and emptied the kilner jar into both. Added a bit of foil on the top and threw them back in the fridge. My idea is to ferment the sugar out and then start the harvesting process again.

Any idea if this is going to work?

 

[shacked]

 

[TimT]

Any ideas if this is going to work?

Yes to both those questions. I do have an idea, and yes, it is going to work!

There's a lot more on this site about yeast washing, growing yeast, storing yeast, re-using yeast which I probably should read as I'm branching out into those areas myself. Anyway, have a look round. Normally I think people just wait until a brew is fermented out, bottle that, and then pitch another beer straightaway on top of the yeast cake.

Since you've only taken part of the yeast, you should probably keep building it up for a bit until you're confident you have enough to add to another brew. Happy yeast farming!

 

[Yob]

Normally I think people just wait until a brew is fermented out, bottle that, and then pitch another beer straightaway on top of the yeast cake

not normal, and not great good practice. Ester development or at least the pathways, largely develop during the growth phase, doing a massive over pitch (whole cake) can lead to a pretty bland sort of beer, you don't get a lot of growth as the large population easily consumes the available oxygen and ferments out rapidly. In an IPA? Possibly, in a Wheat or ESB? No way.

Age old argument here.. people do it and get away with it/stand by it blah blah.. I do not.

Ive used a whole cake once... a few weeks ago when I needed it to get my RIS down below 1040, they managed 10 points before they too perished in the evil black deliciousness.. but in saying that, I wasn't looking for flavor development at that point.. so it has it's place in brewing, just not what is common h34r: