Hydroxycinnamic Acid-Tartaric Acid Ester Content in Mature Grapes and During the Maturation of White Riesling Grapes

A high-pressure liquid chromatographic technique has been used to measure the amount of monocaffeoyl-, mono- p -coumaroyl-, and monoferuloyl-tartaric acids in grapes. The amount of each hydroxycinnamic acidtartaric acid ester has been quantitated on both a ppm and µg/berry basis during the maturation of White Riesling grapes. The concentration of each of the hydroxycinnamic acid-tartaric acid esters and two proposed triesters of caffeic or p -coumaric acid, tartaric acid and glucose is also given for 11 other black and white varieties of V. vinifera at or near maturation.