Quality characteristics and antioxidant activity of juices produced with irradiated grapes

Abstract

The aim of this study was to evaluate physicochemical characteristics, antioxidant activity, total phenolic, vitamin C and anthocyanins content of grape juices from cv. Isabel submitted to different UV-C doses. The fruits were harvested, sanitized and inserted into a UV-C radiation chamber, where different doses were applied: 0 kJ/m2 (0 minutes); 0.68 kJ/m2 (2 minutes); 2.73 kJ/m2 (4 minutes); 4.10 kJ/m2 (6 minutes). The grape juice was extracted at 75±5°C for 1 hour, using an equipment with steam extraction and submitted to evaluations after 0, 30, 60 and 90 days of cold storage. No significant differences were observed in grape juices submitted to radiation doses regarding the antioxidant activity and phenolic compounds. However, the vitamin C content was affected by different UV-C doses, where there was an increase in the values of the treated fruits during storage.