Identification and quantification of anthocyanins in Kyoho grape juice-making pomace, Cabernet Sauvignon grape winemaking pomace and their fresh skin

Background The anthocyanins of Kyoho grape juice‐making pomace, Cabernet Sauvignon grape winemaking pomace and their fresh skin were identified and quantified by high‐performance liquid chromatography–tandem mass spectrometry, and the influence of processing on the anthocyanin profiles was investigated. Results Twenty‐three and 16 anthocyanins were found in fresh skin of Kyoho and Cabernet Sauvignon grapes, respectively. Malvidin 3‐(trans)‐coumaroyl‐5‐diglucoside and malvidin 3‐glucoside were the most abundant anthocyanin in fresh skin of Kyoho and Cabernet Sauvignon grapes, respectively. The cis and trans isomers of malvidin 3‐coumaroyl‐5‐diglucoside are reported in Kyoho grape for the first time. In addition, the anthocyanin content of juice‐making pomace of Kyoho grapes and winemaking pomace of Cabernet Sauvignon grapes was significantly lower than the fresh skin samples (p < 0.05). The percentage variation of non‐acylated anthocyanins was lower than that of acylated anthocyanins in all pomace samples. Conclusion Kyoho grape and Cabernet Sauvignon grape showed distinctive anthocyanin profiles. Juice‐making pomace is a better source of anthocyanins for use in functional foods than winemaking pomace.