I tested a sample of my oregano wine yesterday. The specific gravity is 1.053 and the pH is 2.62. These results are virtually unchanged from 7/13/07 when I first noticed the pH crash that stopped the yeast in their tracks. I’ll try to get them going again by neutralizing some of the acid, raising the pH, with potassium bicarbonate (KHCO3). I had planned on adding two teaspoons because I wanted to add about 10 grams, and I believed that one teaspoon was 4.8 grams. The vendor, Crosby & Baker, says that 1 teaspoon is about 6 grams and warns against using more than 10-13 grams per gallon. That would put two teaspoons, at about 12 grams, very close to the upper limit, and since measuring spoons are not precise I decided to only add one teaspoon this time. I’ll see if fermentation restarts and I’ll retest the pH.
I’ve also decided to add one teaspoon of cream of tartar. The reaction of KHCO3 with tartaric acid will create cream of tartar. By adding some more, I’m seeding the wine and that will encourage the newly created stuff to precipitate out more easily. I’m also hoping it will improve the buffering capacity of the wine.