Effects of storage temperature and duration on physiological responses of pomegranate fruit

Pomegranate fruit (cv. 'Bhagwa' and 'Ruby') harvested at commercial maturity were stored at 5 +/- 0.3 degrees C, 7 +/- 0.5 degrees C and 10 +/- 0.4 degrees C with 92 +/- 3% relative humidity (RH), and at 22 degrees C (65 +/- 5.5% RH) for 16 weeks during which fruit respiration, physico-chemical attributes, antioxidant capacities and incidence of physiological disorders were measured at 4-week intervals. Results showed that the physiological responses and quality of fruit were affected by storage condition, with the maximum levels of respiration occurring at higher temperature and extended storage duration. Fruit color and antioxidant capacity varied slightly among storage temperatures, with total soluble solids and titratable acidity decreasing gradually over time at different temperatures. Although storage at 5 degrees C significantly reduced the total phenolic content of fruit when stored beyond 8 weeks, levels of antioxidant activity in the fruit were not affected. Weight loss was particularly high in fruit stored at 22 degrees C for 4 weeks, ranging between 20 and 25% for both cultivars. Furthermore, the severity and occurrence of physiological disorders were lower in fruit stored at low temperature but increased with extended storage duration. Considering that fruit stored at 5 degrees C and 92% RH had significantly reduced weight loss, low incidence of physiological disorders and best results in maintaining flavor attributes (TSS and TA, TSS:TA ratio), it is recommended that the investigated cultivars be stored at 5 degrees C and >92% RH for 8-12 weeks. (c) 2013 Elsevier B.V. All rights reserved.