Questionable ‘Premium’ Grapes
TroubleShooting
Jim Neame (and the rest of our group) — Victoria, British Columbia asks,
Although I live in Victoria, British Columbia I use California grapes, and this year our winemaking group purchased 8.5 tons. However the pH was all over the map and I am wondering whether or not you could answer the following questions. The “old vine” California Zinfandel grapes tested out as follows: 21 °Brix, pH 3.97, TA 6.2. First question: Is it reasonable to assume the pH from these fields would have been similar last year and would be the same next year? Or can pH be all over the map from year to year from the same fields? The Cabernet Sauvignon had a pH of 3.67, Brix of 22.5 and a TA of 6.0. The Merlot had a pH of 3.8, Brix of 23.4 and a TA of 6.0. In all cases I added tartaric acid to reduce the pH for a total of 4.0 cc per liter for the Zinfandel, 2.5 cc per liter for the Cabernet and 3.0 cc per liter for the Merlot. I would very much appreciate your comments as I am having a serious argument (perhaps a misunderstanding) with the supplier who calls these grapes “premium.” Should grapes with a pH as high as this still be promoted as “premium,” which has also attracted a premium price.