Dealing With Acid Issue on a Raspberry Wine
Jeff Davis — Mount Pleasant, South Carolina asks,
I need help in solving a riddle with a high titratable acidity (TA) and medium-high pH raspberry wine. I am aging This raspberry wine currently and the TA, post- fermentation is about 13.4 while the pH is 3.6. That seems pretty far out of line with what normal wine specs are and I’m not sure how to deal with it. Also of note, I added some calcium carbonate and the pH/TA balance didn’t react like I expected it would. What do you recommend for continuing treating/aging of this wine?
Here’s an outline of what I did (edited for length): Prior to fermentation, I added the calcium carbonate and after two hours racked into a fermentation bucket. I took a sample and measured the following specs: pH 3.54, TA 11.5, Brix 22.
It looked like the calcium carbonate had worked. I Started primary fermentation using Lalvin 71b and added yeast nutrient. After primary fermentation ended, I racked the wine off the lees into a 6-gallon (23-L) carboy: pH 3.6, TA 13.25 (??) how did it go up?
One week later I racked again: pH 3.6, TA 13.5. I proceeded to degas the wine and added ¼ tsp. of potassium metabisulfite powder and finally placed in a refrigerator to cold stabilize.
So how would The Wine Wizard proceed from here?