Antioxidant content and phytochemical properties of apple ‘Granny Smith’ at different harvest times

Abstract

Understanding the biochemical composition of fruit to be stored could be used as a tool for planning postharvest management to maintain quality and reduce losses of fresh fruit. This study evaluated the effects of harvesting fruit seven days before (H1) and at optimal commercial harvest (H2) on the antioxidant contents and phytochemical properties of ‘Granny Smith’ apples. Both ascorbic acid content (345.6 vs 227.0 mg g⁻¹) and total antioxidant capacity (100.82 vs 82.37 μM  ⁻¹) were significantly higher in H2 fruit, whereas concentration of total phenolics was slightly higher in fruit harvested at H1 (25.34 vs 30.87 mg g⁻¹). Phenolic compounds including catechin, epicatechin and quercetin were significantly higher in fruit harvested at H1 compared with H2. These results showed that differences in antioxidant capacity and concentration of phytochemical compounds are the major factors segregating fruit harvested before and at optimal commercial harvest.

Keywords: antioxidants, apples, harvest, physicochemical properties, vitamin C