Nebraskan
Assoc. Winemaker
I have wondered if adding hi proof alcohol to our wines that had some alcohol, like our making of Port, actually killed the yeast or stunted it into hibernation. So, I made up some yeast in 100 ml of our water at work, added small amount of sugar and very small amount of Fermaid - O yeast nutrient along with a .5 gram of our DV-10 yeast. Why did I chose DV-10?... We have it already opened and use it on a pretty much constant basis for innoculating our ciders we make. We go through so much of it that we buy it in 10kg packages, so I know it's fresh, and viable.
Started it up and hydrated with plain water at first. THEN added the yeast, nutrient and sugar, just enough to get it going and a bit energized.
Then, I used our winery calculator for adding hi-proof alcohol to wine to bring it to any specific EtOH % by volume. Easy to do, you find what you have for alcohol, the volume you have, the strength of the EtOH, and plug those numbers in and you can go from 8% up to 18 % by following the addition volumes. Since I had 100 ml I pretended it was 100 gallons and the alcohol % I set at 0.0% since it was just a starter. My target was 20% ABV. I added the proper ml of alcohol and the fermentation came to a stop, as it does when we do the "brandy" addition to our wines to make into port.
Took it home and labeled it "Yeat in 20% EtOH" and stored it in the fridge for 3 weeks. Settled out nice with a clearly defined yeast sediment at the bottom. Is it dead?
So, I drained out the clear liquid above the yeast and added a volume of water from our RO water faucet in the sink. Added some corn sugar and and a very small amount of Fermaid-O yeast nutrient and replaced the cap....loosely. Did this yesterday evening, and at noon today, I see and active fermentation, and holding to the window(light) I can watch lots of bubbles rising through the liquid. Now, I've got to try this again, just to double check, but this might prove to be an excellent way to store my yeasts in longer terms without any fear of degradation by other organisms, since most things won't grow in 20% EtOH solutions like this.
I've included a picture. Just thought I'd share.
Started it up and hydrated with plain water at first. THEN added the yeast, nutrient and sugar, just enough to get it going and a bit energized.
Then, I used our winery calculator for adding hi-proof alcohol to wine to bring it to any specific EtOH % by volume. Easy to do, you find what you have for alcohol, the volume you have, the strength of the EtOH, and plug those numbers in and you can go from 8% up to 18 % by following the addition volumes. Since I had 100 ml I pretended it was 100 gallons and the alcohol % I set at 0.0% since it was just a starter. My target was 20% ABV. I added the proper ml of alcohol and the fermentation came to a stop, as it does when we do the "brandy" addition to our wines to make into port.
Took it home and labeled it "Yeat in 20% EtOH" and stored it in the fridge for 3 weeks. Settled out nice with a clearly defined yeast sediment at the bottom. Is it dead?
So, I drained out the clear liquid above the yeast and added a volume of water from our RO water faucet in the sink. Added some corn sugar and and a very small amount of Fermaid-O yeast nutrient and replaced the cap....loosely. Did this yesterday evening, and at noon today, I see and active fermentation, and holding to the window(light) I can watch lots of bubbles rising through the liquid. Now, I've got to try this again, just to double check, but this might prove to be an excellent way to store my yeasts in longer terms without any fear of degradation by other organisms, since most things won't grow in 20% EtOH solutions like this.
I've included a picture. Just thought I'd share.
