'Stressed' yeast going bonkers

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Drunkula

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Upfront: Can underpitched stressed yeast go bonkers?

I just brewed a recipe from the Greg Hughes book - the dark wheat. Original gravity 1.060. That's of course too straightforward so I decided to try and stress some yeast to see if I get some mad flavours. While the wort was no-chillin' I took a litre of last runnings at 1.020 (boiled, cooled) and put in (hydrated) 1g of crossmyloof krystalweizen and 0.5g of crossmyloof kolsh and put it on the stir plate for 24 hours. Recipe wanted Kolsh yeast, I wanted wheat turnover time.

Under a day later and the blowoff tube is going mental. I've got it in a fermenter in a ferm-fridge in the shed set for 20c, ambient temperature is 8c and it's running at 21.4c with the lid open, it's actually a ferm-chest freezer. I couldn't resist checking and it's gone from 1.060 to 1.032 in 24 hours. I thought the Inkbird might be misreading so I used my infra red and yep, it's a hottie for what it is. I don't mind that because it's a wheat. When I checked there was a nebulous candyfloss krausen about 4cm above the wort with some flakes of crust, not the thick sort that leaves banding.

So - would the 24 hours on the starter really made it up to a traditional pitch rate and this is just normal shifted over a day, or is there some skeezy gubbins occuring? Could it be infected? I'm guessing my invited yeast would be partying faster than gatecrasher yeast.

EDIT: Forgot to say my efficiency was back to normal and I ended up with 25 litres. I'd dropped it down 6% because I'd been using a lot of oats in the last couple of brews and had some trub loss so bonked it down because I thought I was crap. Even with an extra fine crush and doing a vorlauf (just pouring some from the bottom tap to the top) my wort into the fermenter on this brew is clearer than ever.

Cheers me dears.
 
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chthon

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For starters, I found somewhere on the internet the experience of someone who uses dry yeast, but also uses a microscope to count cells (sometimes), and apparently, using an estimate of 20e9 yeast cells/gram is good to go (even contrary to what the suppliers might say). So this would mean that you started out at 30e9 cells. How much time do they need to duplicate, and how many times would they duplicate on a stir plate in 24 hours?

Second, pitching a really active starter will probably also have its impact. I always try to pitch active starters.

And I see a crystalweizen yeast, that is a weizen yeast. Aren't these also notorious for big kraüsen?
 

Drunkula

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Would be interesting to see if this ferments out fully.
42 hours post pitch it's still offgassing strongly, little chance of oxidation so I decided to take another peep and it's at 1.022, which is 5%. The krausen is thinning out to a thin foam. I left the lid open all night and it had dropped to 18.2c by 7am so I shut it and now it's back to 20.3.

I don't want it to attenuate too far. For a 66.7c mash BeerSmith say it'll finish at 1.014 and be 6.5%. I want to keep some body in it, it being a wheat after all.

Initially I thought I'd mix the kristalweizen with some of the CML Belgian because I started getting used to the funk and enjoying it - then I thought what if other people don't like it... now I think I should have done it because tasting nights might be a way away.
 
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