CHANGES IN FRUIT QUALITY, PHENOLIC COMPOUNDS AND ANTIOXIDANT CAPACITY OF FRESH PRUNES DURING STORAGE

Abstract

Phenolic compounds, anthocyanins and some factors related to the quality of fresh prune were analyzed and their changes investigated during storage at 1°C and 5°C. Fruit quality was maintained for 15 days at 5°C but remarkable internal browning was observed after 21 days. The fruit stored at 1°C showed less internal browning than those at 5°C; however, dehydration and softening were severe at this temperature. An increase in soluble solids and a decrease in titratable acid were observed at both temperatures. Total phenolics content of flesh decreased slightly at 5°C but increased at 1°C after 15 days of storage. Total phenolics and anthocyanins content in peel increased at both storage temperatures. 3-Caffeoylquinic acid was the major phenolic compound in flesh, while 3-caffeoylquinic acid, 5-caffeoylquinic acid (chlorogenic acid) and two major anthocyanins (cyanidin 3-rutinoside and peonidin 3-rutinoside) were the major phenolics in peel. Cyanidin 3-glucoside and peonidin 3-glucoside were also detected in peel. DPPH radical scavenging activities of both peel and flesh were higher than a chlorogenic acid standard and this level of activity was maintained during the storage period.