Apple juice Experiment - Potassium Benzoate

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Nov 19, 2015
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I stopped at a grocery store and found that they had a lot of apple juice on clearance. It was normally $7 per gallon marked down to $1. The contents showed it had both K-meta and K-B above. At that price, I decided to give it a try and bought 6.

With a little bit of internet search, I found the evils of K-B and that ascorbic acid turns it into benzene...which is a bit scary. No ascorbic acid was added to the apple juice but I am not sure now much is actually naturally present. I also found that it is a salt of benzoic acid and tends to be effective at a pH of less than 5.5. My juice turned out to be about 3.5. So, instead of diluting with water, which some recommend, I decided to reduce the acidity and see if I could get it to ferment.

I added a 1/4 tsp of acid reducing crystals at a time and rechecked pH each time. After about 14 doses, it seemed to plateau at about 5.1. It would like keep increasing but it was getting to the point where I was seeing little change between each dose at that point. The pH of the crystals was not all that high in and of itself.

I added yeast energizer and yeast to just one gallon. It kicked off and started fermenting pretty well. So, I put 5 gallons in a fermenter and added 1 tablespoon of acid reducing crystals per gallon and yeast energizer. After a bit, I added the 1 gallon that had the yeast to the other 5. It looked like it was going to start fermenting and so I added 4# of sugar. The SG was 1.05 before I added the sugar and was about 1.08 after. Fermentation still slowed way down and I was afraid it was a flop and considered pitching more yeast.

After 2 days, it's now fermenting slow but fermenting. I'm not sure what I'll do with it after it's all said and done. But thought I'd share.

P.S. My crystals were from Kraus and have been on the shelf a long time. So, results may be different with newer chemicals. And, I wonder what might be better for this purpose. I thought of baking soda, but that sounded like it would be awful tasting.