EFFECTS OF ORGANIC AND CONVENTIONAL GROWTH MANAGEMENT ON APPLE FRUIT QUALITY AT HARVEST

A study was conducted to compare the quality of organically and conventionally grown apples (Malus domestica L., cv. ‘Fuji’ and ‘Golden Delicious’) in Lleida (Spain). The differences in total antioxidant activity, determined by 1-diphenyl-2-picrylhydrazyl (DPPH) assay, were related to the changes in the quality parameters color, firmness, acidity and soluble solids content (SSC). In spite of a slight increase in ascorbic acid in organic ‘Fuji’ apples, no differences in total antioxidant activity were found between organically and conventionally grown apples at harvest. In contrast, organic ‘Fuji’ apples showed higher values of firmness, acidity, SSC, and L* and a* values but lower weight values. Similarly, the organic grown ‘Golden Delicious’ apples exhibited the same increases but only when the fruits were picked later. At both harvest dates, organic ‘Golden Delicious’ apples were significantly less mature (lower starch index), but not the ‘Fuji’ apples. Collectively these results showed that organic management may delay on-tree fruit ripening and also improve the fruit eating quality.