ANTHOCYANIN PIGMENTS IN TROUSSEAU GRAPES

SUMMARY: The anthocyanin pigments in Trousseau grapes were extracted with 0.1% HCI in methanol, purified with Dowex 50 WX 4 cation exchange resin in the hydrogen form, and further purified by paper chromatography. Identificaton of the pigments was based on R1 values in various solvents, partial acid hydrolysis, sugar moiety, alkaline degradation, fluorescence under ultraviolet radiation, color reactions, and absorption spectra in the visible region. Shown to be present in the grapes are petunidin 3‐mono‐ glucoside, cyanidin 3‐monoglucoside, malvidin 3‐monoglucoside, and peonidin 3‐monoglucoside. Based on photodensitometric measurement, malvidin 3‐monoglucoside was present in largest amount (49.8%), followed by peonidin 3‐monoglucoside (36.9%), cyanidin 3‐monoglucoside (8.75%), and petunidin 3‐monoglucoside (4.55%). The identification of all the anthocyanins as monoglucosides supports the classification of Trousseau as a cultiva of Vitis vinifera. Copyright © 1969, Wiley Blackwell. All rights reserved