Well, after having racked both carboys of wine several weeks ago, I thought it was about time I ran some labs on them.
So I took some samples to school and ran SO2‘s, pH and TA (titratable acidity) tests, as well as doing a chromatography test on them. This test tells me whether the wines have converted malic acid to latic acid. Malic is a harder/sharper acid; think sour apple. Lactic acid is much softer. As I suspected from tasting as well as watching pH and TA’s go up and down, it looks like the Petite Verdot/Cabernet Sauvignon blend have almost completely converted to latic acid. The Sangiovese/Cabernet Sauvignon still have a way to go.
After going through all the trouble of running an SO2 test on my wines, I realized that I had used the wrong strength of NaOH, so I’m still not sure how much free SO2 is present. So I decided I will run them again once they are through with malic/latic conversion. I won’t want to add any now anyway, since that would stop the conversion process.