Can You Freeze Wine Yeast? And For How Long?

Many years ago, I had a popular website and blog that focused on winemaking. Back then, there were probably half a dozen websites devoted to the hobby and art of winemaking including Jack Keller’s site (which sadly seems to be offline now). While not an expert at home winemaking (you’ll have to get in touch with Daniel Pambianchi if you want a true expert), I have had many years experience reading, studying, experimenting, making great wines while also failing at some. I learned from those more than I learned from the wines that turned out great.

The site had sections devoted to explaining the wide variety of wine yeasts (and their characteristics), as well as sections aimed at beginners and enthusiasts alike. A few things happened along the way, and around 2008 or 2009, my winemaking hobby took a back seat to some other things. At the same time, I was discouraged as many others, trying to capitalize on what would become a more popular hobby, had created their own sites around the subject of winemaking and had plagiarized many of my articles and posts – not only that appeared on my old website, but even those articles that had been published in periodicals relating to wine and winemaking.

I ended up letting the domain name I had go, which I now regret as the homewine making bug has hit me again. It’s great to share the various techniques with my beautiful Greek partner, who has some experience also in making wines in Greece in the traditional manner at the village her family is from!

Anyhow, this leads me to some thoughts on wine yeast and some myths I have read recently about storage.

Is It Safe To Store Wine Yeast In The Freezer?

Recently I came across a “self-appointed” expert on winemaking (he owns a fairly new “Brew Your Own Beer” shop) and after reading some of what he had written, I can tell that he really did not know a lot. He claimed that you should never ever freeze your yeast. He had some strange reasoning for this that I had never heard of – but I did not bother to research his reasons further, as the fact is, it is safe to freeze winemaking yeast. I’ve done it many many times!

The trick is… how long can you store it in the freezer for? I don’t know exactly, but I think this depends just on how cold your freezer is. The colder, the longer it will safely store and remain viable, I believe.

How do I know this? I don’t make claims about anything unless I’ve researched it fully myself, and in many cases, unless I’ve actually tried it. So today, I’m going to tell you that it is possible, that wine yeast that you put in the freezer 10+ years ago, could still be viable! Because this week, that is exactly what I have discovered from personal experience.

Cote de Blanc Yeast Stored For Over 10 Years

Cote de Blanc yeast is a slow fermenting yeast and is often preferred for fruit wines. It will work between 50F and 86F but ideally, above 64F and below 80. It is often used when a wine with some residual sweetness is desired (as is often the case for fruit wines, but not always).

As mentioned, the home winemaking “bug” had hit me again, and I had some frozen blackcurrants (I made an incredible wine once with these berries, many years ago) and I wanted some D254 yeast for it. I had asked my local winemaking shop if they might be able to get it, when I recalled that it was not typically available in small packages but was packaged in half kilogram units, more aimed at commercial winemakers.

I knew that I had purchased quite a bit of it years ago; was it possible some was still in the freezer?

Well, I went digging to the bottom of my freezer, and indeed I found quite a few different strains of yeast that I had forgotten I had purchased. Several packets were Cote de Blanc as well as the D254. But would they work? As much as I wanted to start a blackcurrant wine, I also had a gallon of apple cider… which the Cote de Blanc would be perfect for. And an easier thing to start than to create a must from frozen blackcurrants.

I took out the packet of Cote de Blanc and had my doubts. The expiry date on the package was “April 2008.” Yes – it had expired almost 11 years ago. That meant it had probably been in my freezer for at least 12 years!

I poured about half a cup of warm water into a measuring cup and sprinkled the yeast on top to re-hydrate it. After about 15 minutes, I added a teaspoon of dextrose (corn sugar) and a pinch of yeast nutrient. I still had my doubts….

Half an hour later, I was pleasantly surprised to discover that there were bubbles – CO2 bubbles – the yeast was working!

I opened up the apple cider (containing no potassium sorbate, thank goodness), warmed it up so I could dissolve more sugar to raise the specific gravity (and potential alcohol level), then poured it into a small pail, and pitched the yeast. I now have apple cider fermenting into wine, from yeast that is very very old!

D254 Yeast Passes The Freezer Test Of Time

As mentioned, my original goal for the week was to get some D254 and make plans to start the blackcurrant wine. As mentioned above, I found some of that yeast as well in the freezer (in the same box as the Cote de Blanc and other strains). Today, I took it out and wondered how this particular strain had handled the 12 years in the deep freeze. Like the Cote de Blanc, I sprinkled it into some warm water to allow it to hydrate, then added some dextrose and pinch of yeast nutrient.

Could I be so lucky as the first time?

“Holy smokes!” I exclaimed out loud. “It is working!” Sure enough, there was vigorous activity going on in that measuring cup. So I scrambled to prepare my frozen blackcurrants into a must, pitched the yeast, and hours later, lots of wonderful activity is going on as the yeast feed on the sugars, creating alcohol and CO2 as the byproduct.

There’s more to the whole blackcurrant wine making process but that’s for another post. The big lesson here is….

Don’t listen to experts that are not experts. Experiment and research yourself – it is possible that the old packages of wine yeast at the bottom of your freezer still might be viable, even a decade or more, later!

Crazy Wine Experiments

Now that I’ve done this, I’m going to get back into my “crazy experiments” as some call them. Not only have I made grape wines, I’ve tried quite a few different things, including “country” wines from fruits and berries, garlic wine (not for sipping but for cooking with), and even vegetable wines such as potato and parsnip. Don’t laugh – that parsnip wine was amazing and a perfect compliment to Indian curry dishes. People who tried it did not even realize it was not a grape wine until I told them.

But now, we’re going to try oregano… not just any oregano, but true Greek oregano wine – I came across the idea earlier; I do not expect it to taste very good… but who knows until I try? Perhaps it will be very good for cooking with, like the garlic wine.

But for now, I’m pleased that my investment in yeasts many years ago has paid off with the deep freezer, regardless of what some experts claim.

I still have all the content and database from my old winemaking website; I may find a way to republish it all, perhaps under a new domain name or a subdomain of ianism.com. I have not decided yet.