Transpiration rate and quality of pomegranate arils as affected by storage conditions

This study investigated the transpiration rate (TR) of pomegranate (Punica granatum L.) arils under various combinations of temperature (5, 10 and 158C) and relative humidity (RH) (76, 86 and 96%) during storage. Transpiration rateTR ranged from 1.14 to 16.75 g/kg day across the various combinations of RH and temperature studied. Relative humidityRH had the most significant impact on TR (p 5 0.05). Transpiration rateTR increased six-fold when RH was reduced from 96 to 76%, and correlated well with water vapour pressure deficit (WVPD) (R2 = 96.1%). Aril weight loss increased at higher WVPD. After 8 days of storage, losses in quality attributes of arils were higher with increasing storage temperature and lowering RH. A mathematical model to predict TR as a function of temperature and RH was developed and successfully validated at 88C. The target water vapour transmission rate of packaging materials for pomegranate arils was found to be 33 to 68 g/m2 day.