I got my order and the yeast were in a bag along with the hop packets. I tossed the bag with the hop packets into the freezer. 4 days later, I check the bag and discovered that I did not remove all of the yeast. The White Labs WLP833 in the PurePictch was also in there. It was frozen solid, hard as a rock.
I have thawed it in my refrigerator.
Is there any hope?
Thanks in advance.
So, I’m sure you’re tired of hearing this, I get tired of it as well [emoji28] but Brülosophy froze some yeast, made a beer, and it was indistinguishable from the non frozen yeast beer [emoji28] YMMV. I wonder about some of the things but I haven’t tasted their beer, just reading an article, so what do I know.
Not to mention that was a single trial, not a scientifically valid conclusion.
I’d say there’s at least a chance it might work. Make a starter and that will tell the story.
Apparently it depends… https://aem.asm.org/content/aem/63/10/3818.full.pdf If it were me I’d take Denny’s advice and make a starter
Freezing won’t kill all the yeast. Just make a starter it will most likely be fine.
I’ve had Wyeast Smack Packs left outside in a cold snap that got slushy (although never frozen solid), that I smacked a few days later after thawing. They puffed up like normal and worked just fine.
Add me to the “make a starter first, but it will probably be fine” list.
Yes, this is a single data-point, but there is no evidence to indicate this is not repeatable.
I might try freezing a harvested slurry, keep it for 6 months, and then proceed to brew with it. As an experiment, to get another single-data point on the success or non success of this approach.
And if it pans out, I would consider freezing more yeast that I wish to store for extended periods.
There is no evidence either way…there’s a reason that yeast is frozen mixed with glycerin
Thanks for the advice. My standard procedure is to make a starter. I like using the Propper Starter.
Cheers
I save some wort from the previous brew, and use that for a starter to feed yeast that is dormant. No, it is not as high in sugar content as making a starter using DME, but it does work. I boil the wort for 15 minutes, chill it to 70 degrees, and then add it to my yeast slurry. Works like a charm. And it is free…sort of.
Looking forward to freezing some yeast, just to see what happens.
If you don’t have the “Yeast” book by White and Zainasheff it’s worth the read and will tell you how to freeze yeast with glycerine (IIRC) but if you want to just freeze yeast for the hell of iot well, why not? Yeast survives freezing temps otherwise wild yeast wouldn’t thrive anywhere except the tropics. The problem with freezing is that the water crystals act like tiny shards that break the yeast’s cell membrane -glycerine fixes that problem. I’d put money on some survival, probably won’t be in great health though.
The thing that one has to worry about with freezing are cell walls bursting. Anyone who has frozen water knows that is expands when frozen. Part of the yeast freezing process is adding a cryoprotectant, usually glycerol.
That being said, I am willing to bet that more than a few cells survived the ordeal. I would pitch the yeast into a 1L 1.030 starter and see if it starts within 24 hours.
I suppose that’s why fresh beef, and fresh fish is always better than frozen.
Not necessarily with fish and many veggies. Frozen is often as good, if not better.
Slightly off topic, but having done a lot of fishing on the Canadian border over the last 45 years, and catching awesome Walleye Pike, I can testify that the fish we catch and eat right away is far better than what we freeze and then vacuum seal, and eat at a later date.
Your experience may differ.
Off topic back at ya - Agree that fish you catch is better but frozen is almost always better than “fresh never frozen” fish that has travelled for days. I think that is what Denny is talking about. If I’m at the beach I better not be eating frozen fish!
Exactly. Plus commercial fish is generally flash-frozen, which generally bypasses the problems of ice crystals tearing cell membranes that happens during a slower freeze.
So, are we in agreement for the average brewer that fresh yeast is probably better than frozen yeast?
I think that liquid yeast which has never been frozen is likely to be as good, or better, than the same yeast that has been frozen (partially or completely).
I made a starter with the previous frozen yeast. No activity. It’s toast. Thanks for the replies!