Extending the shelf life and maintaining quality of minimally-processed pomegranate arils using ascorbic acid coating and modified atmosphere packaging

Abstract

Demand for minimally processed ready-to-eat pomegranate arils increased in the market over the past decade due to their high nutritional value, sensory characteristics, convenience, and health benefits. The objective of this study was therefore to investigate the effect of ascorbic acid coating and modified atmosphere packaging (MAP) on the physicochemical, microbiological, sensory quality characteristics and shelf life of pomegranate arils Shishe-Kab cultivar. Treatments were: passive-MAP, passive-MAP (washed arils with water), active-MAP1 (35.2% O2, 0.3% CO2, 64.5% N2), active-MAP2 (15.5% O2, 20% CO2, 64.5% N2), active-MAP1 + ascorbic acid, and active-MAP2 + ascorbic acid. The results indicated that experimental treatments significantly influenced some of the physicochemical parameters of pomegranate arils as pH and redness increased. A combination of active packaging (MAP1 and MAP2) and ascorbic acid coating preserved the redness of arils and had higher a* values compared to control and other treatments after 20 days of cold storage. Interestingly, samples packed in active-MAP with or without ascorbic acid coating helped to keep the sensory qualities with acceptable eating quality, as well as significantly extended the shelf life (about 30%) of pomegranate arils ‘Shishe-Kab’ cultivar in refrigerated storage at 3 °C compared to passive MAP. In conclusion, the results revealed that higher O2 or CO2 concentration than air in packages (active-MAP) alone and plus ascorbic acid coating can prolong the lag time of microorganisms and extend the shelf life of pomegranate arils more than 20 days during cold storage at 3 °C. Overall, sensory scores were also higher in ascorbic acid coated arils that were quite acceptable even after 20 days of storage at 3 °C.