The aim of the work was to follow the behaviour of both vitamins, thiamine and riboflavin, during ripening of Vitis vinifera Cabemet Sauvignon and during fermentation of the must using different amounts of SO2. Minimum values for thiamine and riboflavin were, respectivelly, (ug/100ml): 7.67 and 6.85 at 5.5 °Brix and the maximum values were, respectivelly, 19.35 (at harvest) and 15.75 at 12.87 °Brix. Thiamine was almost completelly consumed before the start of fermentation showing up again at the end of the process; riboflavin, on the contrary, increased during fermentation. Both vitamins increased during ripening of Cabemet Sauvignon but -in grapes- the amount of thiamine was greater than riboflavin. Fermentation procedures, as increasing levels of SO2, affected thiamine in a direct proportion but did not have any effect upon riboflavin. Thiamine decreased during fermentation and riboflavin increased.
thiamine; riboflavin; cabemet sauvignon; fermentation; ripening
