The effect of melatonin applications on storage performance of blackberry

This study was carried out to investigate the effect of different doses of melatonin (50, 100 and 150 μmol/L) on postharvest quality parameters in Jumbo blackberry cultivar. For this purpose, weight loss rate, decay rate, fruit flesh firmness, fruit colour characteristics, water soluble dry matter (SSC), titratable acidity, pH, total phenol, total antioxidant capacity and total monomeric anthocyanin content were determined. After the blackberry fruits were harvested, they were brought to Tokat Gaziosmanpaşa University, Faculty of Agriculture, Department of Horticulture, Fruit Growing Laboratory. The fruits were sprayed with four different doses of 0 (Control), 50, 100 and 150 μmol/L melatonin solution and left to dry. The fruits were then stored in cold storage at 2±0.5 °C and 85±5% relative humidity for 15 days. Fruit quality parameters were measured and analysed at three-day intervals (0,3,6,9,12 and 15 days) during storage. As a result of the study, it was determined that weight loss increased during storage and the lowest weight loss was in 100 μmol/L melatonin treatment. Decay started on the 9th day of storage and it was determined that 100 and 150 μmol/L melatonin treatments slowed down the decay. pH values decreased during storage and all melatonin applications prevented the pH value from increasing. TA values decreased during storage and 100 and 150 μmol/L melatonin applications slowed down the decrease in TA. SSC amount decreased during storage and 150 μmol/L melatonin slowed down this decrease. Vitamin C content fluctuated during storage and generally decreased. However, 50 μmol/L melatonin application increased the amount of vitamin C. While total phenolic content decreased in other treatments, it increased in 100 μmol/L melatonin treatment. Total monomeric anthocyanin and total antioxidant activity decreased during storage and 50 μmol/L melatonin application slowed down the decrease. It was determined that melatonin applications had no effect on L*, a* and b* values. Melatonin applications had no effect on fruit firmness and RDR ratio.