I’ve always heard that a yeast slurry should be used within a few weeks. I’ve used them past a month with good success. I have a slurry that’s is two months old. I have plenty of it. It’s the exact yeast I would buy so I was thinking why not use the slurry. Anyone reuse yeast this old? If I make a starter would that help to revive the yeast? or is it too old and just get more Yeast. The yeast slurry was poured directly from the fermenter into mason jars. Has a low gravity beer as the liquid. cheers
I tried this exact thing with a mason jar of , let's call it trub actually - because to me slurry is more like pure yeast, say from a starter. In short, it did not work for me. I put it on a stir plate in a starter and it did absolutely nothing... IIRC, it was around the two month mark. I think for a slug of trub out of the fermenter, you want to pitch it in a week or maybe two max...
Yeast slurry is just like any yeast, in the respect that the older it is, the more has died off. BrewCipher supports yeast slurries. Just enter the number of milliliters of slurry and the age on Recipe tab, and it will recommend how much slurry to use (or recommend a starter if there's not enough). There are also a couple of slurry parameters on the Brewhouse tab which you can tweak if values other than the defaults fit your slurry better (see the mouseover popup help for those cells).
I've used much older slurries with no issues. It may need a multi step starter but in my experience is just fine.
I’ve had good success with this process before with yeast trub before around the month mark. Just not this old. Thanks for the feedback.
thanks. I always use brewchiper to enter in my yeast trub/slurry. I’ll have to calculate it and make sure I have enough. I do Have two full mason jars and doing a moderately low abv beer.
My instinct says you have plenty of yeast here, but I guess it depends -- what size jar are you talking about? I got canning jars that range from half a cup to half a gallon.
I replied to myself, above haha. I meant to reply to you. Thanks that’s exactly what I was hoping to hear.
I have found after a month, I feed the slurry with a bit of sugar, just a half teaspoon . It can b quite explosive at times , but keeping it in the coldest part of the fridge helps.
It depends on the yeast. Some strains will lose viability rather quickly, others not so much. English ale yeasts seem to be the least hardy but that’s a bit of a generalization. I would take a tablespoon of the slurry and make a large starter and dump the rest. You don’t want to dump a bunch of dead yeast into the fermenter in hopes of getting a small percentage of healthy ones. It might take a bit longer than normal or you might want to make a two step depending on the beer. A little yeast nutrient in the starter might be a good idea as well.
I ended up dumping the yeast slurry into the fermenter based on brewchiper’s cell count. It’s a lager yeast and doing the fast ferment, 58 a few days then raising. I’ve had good success using this yeast, WLP830 German Lager, and fermenting warmer than traditional. Doing my version ok Oktoberfest, more like a Sierra Nevada version. Lighter and bit more hoppy than most. But plenty of Vienna to give it some toasty notes. Fermenting away nicely. I’ll give an update on taste for anyone who searches for the same topic. Cheers free image hosting
I made several batches of beer reusing WLP830 in the spring of 2019 and saved a few mason jars of slurry/beer in the fridge. In early spring 2020 I restarted the yeast and have been repitching it throughout the summer with some of the best lagers I have ever brewed (granted I’ve added others steps and processes at the same time like kräusening) but the yeast has been doing it’s job and I’m using it again this weekend.
