Total antioxidant activities, phenolics, anthocyanins, polyphenoloxidase activities of selected red grape cultivars and their correlations

Sixteen red grape cultivars (Md. Jean Matthias, Öküzgözü, Muscat Hamburg, Cabarnet Sauvignon, Tekirdağ Çekirdeksizi, Gewürztraminer, 2B/56, Kalecik karası, Carignan, Kokulu Siyah, Alfonse Lavallée, Boğazkere, Adakarası, Papazkarası, Mourvedre and Cinsaut) which are grown in Tekirdağ Viticulture Research Institute were analyzed for determination of antioxidant activities, total phenolics, anthocyanins, external colour, polyphenoloxidase activities, sugar and acidity. The lowest antioxidant activity (percentage of inhibition on peroxidation in linoleic acid system; AA) was determined in Tekirdağ çekirdeksiz extracts as 87.58% and the highest AA was in Mourvedre (93.78%). Total phenolic content (TP) varied from 817 to 3062 μg/ml GAE in the same varieties, respectively. The total anthocyanin (TA) content ranged from 40.3 to 990.8 mg/l fresh weight. The lowest PPO activity was found in Boğazkere and the highest was in Kalecik karası. The total sugar content in the analyzed varieties varied between 13.29 and 24.46%. There was stronger correlation between AA and TP than AA and TA.