1,2,3,4-TETRAHYDRO-BETA-CARBOLINE-3-CARBOXYLIC ACID AND 1-METHYL-1,2,3,4-TETRAHYDRO-BETA-CARBOLINE-3-CARBOXYLIC ACID IN WINES

1,2,3,4-Tetrahydro-beta-carboline-3-carboxylic acids were analyzed in 16 table wines, 34 old and new dessert and aperitif wines, 8 sparkling wines, 18 distillates, and 5 grape juices. The concentration found ranged from 0 to 17.8 mg/L for 1-methyl-1,2,3,4-tetrahydro-beta-carboline-3-COOH (MTCA) and from 0 to 0.65 mg/L for 1,2,3,4-tetrahydro-beta-carboline-3-COOH (THCA). Higher concentration was generally found in fortified wines than in table wines and very low or no concentration at all in distillates and grape juices. No correlation was detected between the two tetrahydro-beta-carboline-3-COOHs and the concentration of tryptophan or acetaldehyde in the wines. However, a good correlation in the formation of tetrahydro-beta-carboline-3-COOH was found when tryptophan or tryptophan and acetaldehyde were added to a sherry and a white wine, respectively. This may be due to the blocking effects of sulfur dioxide that would be variable from wine to wine. This effect will be reported on later.