Characterization of selected organic and mineral components of qvevri wines

The organic and mineral components of 20 qvevri wines from selected wineries throughout Europe were evaluated to gain insight into one of the oldest known methods of wine production. The pH, residual glucose, titratable acidity, specific organic acids (acetic, lactic, malic, and tartaric acids), phenolics (total phenolics and anthocyanins in red wines), total antioxidants, and selected minerals (phosphorus, calcium, magnesium, manganese, potassium and zinc) of the samples were measured. The data were compared with previously reported values for conventional wines. Qvevri wines were less acidic than conventional wines, containing higher levels of acetic and lactic acids but lower levels of tartaric acid. They also contained higher levels of antioxidants and total phenolics, the latter up to 10 times more abundant in the white wine varieties than in conventional wines. Despite fermentation in clay vessels, the mineral content of qvevri wines was within the normal reported range, although phosphorus levels were slightly higher. This is the only study that has considered the compositional nature of qvevri wines.