INFLUENCE OF CULTIVAR, MATURITY STAGE AND GEOGRAPHICAL LOCATION ON THE JUICE PIGMENTATION OF TUNISIAN POMEGRANATES

The anthocyanin pigmentaion of the juices obtained from six Tunisian pomegranate cultivars harvested at commercial maturity was studied by HPLC. The anthocyanin content in the juice ranged between 6 mu g/ml and 120 mu g/ml. Six anthocyanins, namely the 3-O-glucosides and the 3,5-diglucosides of pelargonidin, cyanidin and delphinidin, were detected in all samples. Differences in the relative amounts of each anthocyanin were found for the different cultivars. The total amount of anthocyanin pigmentation of pomegranate juice was largely affected by the variety, the maturation stage and the geographical location of the fruit, but the anthocyanin profile remained quite stable under the different conditions. The anthocyanin profile constituted by the six pigments seems to be identical to those reported previously for Californian, Spanish and Italian pomegranates, and only differences in the relative amounts of the individual anthocyanins could be related to the variety and other climatic and cultural variables. These data suggest that the HPLC anthocyanin profile of pomegranate juice could be used as an adjunct in its analytical characterization, and in the differentiation with other anthocyanin-containing juices in food authenticity studies.