Effects of sucrose and copigment sources on the major anthocyanins isolated from sour cherries

Cyanidin-3-O-glucosylrutinoside and cyanidin-3-O-rutinoside were isolated from sour cherry juice concentrate (SCJC). Sucrose and copigments [gallic acid (GA), cherry stem extract (CSE) and pomegranate rind extract (PRE)] were added to these anthocyanins. Effects of sucrose and copigments on the isolated anthocyanins were studied during storage at 20 degrees C for 140 days. All copigment sources provided protection against degradation effect of sucrose on the isolated anthocyanins before storage. Although GA increased the stabilities of both isolated anthocyanins, only CSE had copigmentation effect on both isolated anthocyanins. Copigmentation effect on cyanidin-3-O-glucosylrutinoside continued throughout storage. However, this effect on cyanidin-3-O-rutinoside continued for only 56 days of storage. Cyanidin-3-O-glucosylrutinoside containing three sugar moieties was more prone to copigmentation than cyanidine-3-rutinoside containing two sugar moieties. Results showed that the presence of more than one anthocyanin in a media changed stability of copigmentation. We recommend CSE for enhancement in colour density, but GA for enhancement in anthocyanin stability.