Effect of Hot Air Treatment on Physio-Chemical Properties of Pomegranate Arils

Abstract

Hot air treatment has been applied on a wide range of horticultural crops to control postharvest decay and to maintain quality characteristics. To evaluate the effect of hot air treatment on physio-chemical properties of pomegranate arils, an experiment was carried out in a factorial experiment using a completely randomized design with four replications in 2015. About 200 g of ‘‘Rabab-e-Neyriz’’ pomegranate arils were placed in 350 mg polypropylene boxes with three holes on top for ventilation. Boxes were heated at 35 °C, 40 °C and 45 °C and 80% relative humidity for 30, 60, and 120 min in oven. After being cooled at an ambient temperature, boxes were stored at 5 °C (RH= 70-80%) for 15 days. The scored results of decay assay showed that heated “Rabab” arils at 35 °C till 45 °C decayed lesser than those untreated during storage period. Hot air temperature at 45 °C for 120 min resulted in the highest weight loss at the end of storage period. The highest total soluble solids content was belonged to the arils heated at 45 °C for 30 min. Hot air treatments increased pH and TSS/TA ratio of aril juice. Hot air temperature treatment decreased antioxidant activity, total phenolic compounds and total anthocyanin of arils during storage period, whilst hot air treatment had no significant effect on color values. Generally, the application of mild heat treatments could be considered as a non-contaminant postharvest tool to maintain functional and nutritive properties of arils during postharvest storage.