Growing yeast

[mikewatkins727]

I am finding yeast in short supply. Was thinking of growing a yeast culture for my needs but would like some input and advice from the community. Any takers on giving me advice?

 

[TonyP]

I'm pretty adventurous but couldn't imagine growing yeast for wine. I try to find the proper yeast to compliment my wine and fit my temperature needs. There are plenty of yeasts available online if your local supplier has difficulties.

 

[ZebraB]

I would agree with TonyP but perhaps you are trying to find bread yeast at the stores. If so, then the tread below can help you with growing sourdough yeast

https://slice.seriouseats.com/2010/11/how-to-make-sourdough-starter-day-0.html

 

[1d10t]

Yeast: The Practical Guide to Beer Fermentation (Brewing Elements)

Lots of good knowledge. One of the authors is Chris White of White Labs. You can check out homebrewtalk.com . You'll find people that keep yeast banks of different strains.

 

[G259]

Are you in an area that isn't hospitable to the wine trade? I have encountered that before, and feel the pain if so.

 

[BernardSmith]

If you are making large volumes of wine or you are making wine that for whatever reason needs to be consistent from batch to batch then trying to capture and use indigenous yeast may be a greater headache than it may be worth but if you are a hobbyist and your goal is to make small batches of country wines, that is to say, wines from local fruit and vegetables and the like then growing and harvesting local yeast cultures is not such a terrible problem. But there are two or three things you may need to know.
1. Yeast covers just about every organic material but so do bacteria and not every strain of yeast will produce flavors that you will like.
2. Find yourself some fruit, could be any fruit from raisins to berries or from apples to dates and wash them (or not). If you wash them then allow them to sit in your kitchen for a few days after you have dried them.
3. Initially, you are not trying to make a wine but to grow the colony of yeast so you want to cut the fruit into small pieces, mash it even, and then pour over the fruit about 1000 L of non chlorinated water. To this water you want to add enough sugar to raise the density of the water to about 1.040 (so that is going to be about 4 oz (100 g) and you want to shake the container so that you add lots of oxygen to this mixture. And you want to shake it vigorously two or three times a day for two or three days. After a few days you should see bubbles rise and you will need to find some way to allow the gas (CO2) to escape but prevent dirt and air from entering.
4. After about a week smell the mixture. If it is not unpleasant taste it. If it tastes OK try adding more sugar - say, 50 g, and observe over the next few days. The yeast may not be able to ferment this because they have reached their tolerance for alcohol. So this batch is not going to make your wine. But some of the yeast may still be active and it may take them a few more weeks to finish that sugar.
5. If the yeast are able to finish the job then you might want to harvest this batch. Check out Youtube videos on harvesting and washing yeast. But basically the idea is that after yeast have finished fermenting they tend to drop out of suspension. You can help them do that (wild yeast are not as good as that as lab cultured yeast) by storing your jar in a fridge for a couple of days. The cold makes them drop. You pour out the liquid holding back the lees and then you add sterilized water (boiled and cooled) to the lees to allow the yeast to collect on top of the other waste products they have produced from the sugars you had added. For all intents and purposes the white sediment that you see is yeast and you can store this in sterilized (beyond sanitized) mason jars in your fridge until you have the fruit or material you want to make into wine. When you have your must you decant almost all the liquid and add the sediment to your fermentables and voila! you will have a large enough colony of yeast to ferment your fruit.
6. I would be conservative. You may find that the yeast will give up the ghost when your wine is at 6% ABV or 8% but what you want to do is select the yeast for higher and higher ABV wines so that each time you make a successful batch from the same colony of yeast you make sure that the next batch of wine you make has a little more sugar for the yeast to ferment and so you encourage the more viral and alcohol tolerant yeast to reproduce and those that are less alcohol tolerant won't be in the next batch reproducing.
BUT most importantly, many of the colonies you may grow may make wines whose flavors you really don't like - but that is the cost of doing business because SOME of the wines will have flavors that you may love and they will be uniquely yours.

 

[G259]

OK a while back, I had a wine ready for pitch, but had to wait a few days to acquire some yeast. It took off before I could get some, and was told that it was from indigenous yeast, from previous fermentation. If so, do I even need to buy yeast? (at $1 a packet, not an issue. just minus a step)

Sorry, but that sounds like a lot of work, I think I'll buy mine! (not downing, just lazy!)

 

[BernardSmith]

I don't consider myself an expert when it comes to indigenous yeast but I do like to explore the possibilities. That said, I would suggest that you MAY want to pitch lab cultured yeast after you have allowed the indigenous yeast a few days to sample the sugars. While it is perfectly possible the wild yeast will have the ability to fully ferment the must, the probability is not high but allowing the juice to be fermented for a few days will certainly add complexity to your wine that in some sense money cannot buy.

 

[DizzyIzzy]

Are you in an area that isn't hospitable to the wine trade? I have encountered that before, and feel the pain if so.

What do you mean inhospitable?

 

[G259]

What do you mean inhospitable?

In some countries alcohol is frowned upon, some more than others.