Bottling With Harvested Yeast

[Bobo1898]

Made a saison a few weeks ago and it's close to packaging time. I tend to bottle condition my saisons. In the past, I've always pitched brand new yeast.

This time, I decided to harvest some yeast since it was a blend of two strains. 48 hours after pitch, I top cropped my krausen and put the yeast aside in some distilled water in the fridge. I had open fermented around 66 when I harvested this. After that, I closed the fermenter and pushed the temp towards hot. My concern was, the krausen I skimmed wasn't particularly thick and therefore, I didn't feel I was getting much yeast.

I know there's probably still a lot of yeast in suspension in the beer, but it was pushed to 95 degrees so I'm inclined to take it off that. I'm currently cold crashing it.

If I wanted to step up the harvested yeast, is a 500ml starter too much for bottling? Should I even bother with it and just get new yeast?

 

[VikeMan]

I know there's probably still a lot of yeast in suspension in the beer, but it was pushed to 95 degrees so I'm inclined to take it off that. I'm currently cold crashing it.

You are right. There is still plenty of yeast in suspension. Do you think 95F during fermentation damaged the yeast? I doubt it. Also, cold crashing will remove some of that yeast, but not all of it. There will still more than likely be enough left to handle carbonation. My point is that you can't really "take it off that."

If I wanted to step up the harvested yeast, is a 500ml starter too much for bottling? Should I even bother with it and just get new yeast?

How much yeast you get from a 500 ml starter will depend on how much you start with. But the idea of doing a starter to increase a cell count for bottling seems a little nutz to me. If you have enough harvested yeast to actually reach critical mass in a couple days in a 500 ml starter, then you already have more than enough to carbonate without the starter. You need maybe 5B cells to carbonate a 5 gallon batch. That may sound like a lot of yeast, but it's not.

Keep in mind that people successfully carbonate lagers using residual suspended yeast after weeks or even months of lagering.

Disclaimer: I not guaranteeing anything. But given the information in the OP, rolling with yeast still in suspension is what I would do if this were my beer.

 

[Bobo1898]

Thanks for the response!

You are right. There is still plenty of yeast in suspension. Do you think 95F during fermentation damaged the yeast?

I was under impression that higher temps can speed up autolysis. It's not at that phase now, and I don't know the rate metrics of autolysis in general. I mean, hopefully I'm drinking my beer at a faster rate. Saisons and other Belgian beers will tend to age in the bottle for extended periods of time in my cellar, hence the slight concern, for as much as a year.

If you have enough harvested yeast to actually reach critical mass in a couple days in a 500 ml starter, then you already have more than enough to carbonate without the starter.

Perhaps I'll be fine with what I've harvested. There is a nice layer on the bottom of my mason jar.

 

[VikeMan]

I was under impression that higher temps can speed up autolysis. It's not at that phase now, and I don't know the rate metrics of autolysis in general. I mean, hopefully I'm drinking my beer at a faster rate. Saisons and other Belgian beers will tend to age in the bottle for extended periods of time in my cellar, hence the slight concern, for as much as a year.

From an autolysis standpoint, I'd be more concerned about dormant yeast at cellar temps for a year than I would be about actively fermenting yeast at 95F for a couple weels. In the latter case, I really wouldn't be concerned at all.