Effect of calcium ascorbate on quality changes of ‘Golden Delicious’ apple fruit at cold store

In order to investigate the effect of calcium ascorbate on quality changes of ‘Golden Delicious’ apple during storage, an experiment was conducted in a completely randomized design with three replicates in 2017. The main factor was the concentration of calcium ascorbate (0, 2.5 and 5%) and the sub factor was different storage times (90,150 and 210 days). The results showed a significant increase in total soluble solids, browning index, ethylene production and a significant reduction in total phenols content, vitamin C, titratable acidity, fruit firmness, and fruit postharvest life with increase in storage time. In addition, by the increase in calcium ascorbate concentration, the total acidity, tissue firmness and shelf life were increased (22.31, 17.83 and 8.54 %, respectively) and ethylene production rate was decreased (60.82 %(. The interaction effect of calcium ascorbate and storage time on phenolics content and ethylene production was also significant. The results showed that calcium ascorbate at all concentrations decreased the ethylene production and with increase in storage time, the production rate of the ethylene was increased in all treatments. The highest ethylene production rate was recorded in control fruit after 210 days of storage. However, calcium ascorbate increased the shelf life of apple fruit during storage by slowing the rate of ethylene production and ripening processes.