Studies On Storage Properties And Fresh-keeping Technology Of Ready-to-eat Pomegranate Arils

Pomegranate (Punica granatum L.) is high valued for its nutritional properties andpotential health benefits. However, pomegranate consumption is limited due to difficulties inpeeling to obtain the arils. Therefore, production of pomegranate arils in ‘ready-to-eat’ formwould be a convenient and desirable alternative to the consumption of fresh fruits and mayincrease pomegranate demand by consumers. In this work, Lintong pomegranates were usedas materials and minimally fresh processing was done to obtain ready-to-eat arils. The aim ofthis work was to study the effect of four physical methods, including storage temperature,MAP package, heat treatment and UV-C treatment, on keeping quality of ready-to-eatpomegranate arils. The results indicated that:(1) Pomegranate arils stored at room temperature were difficult to preserve and decayedbadly at the third day of storage, while low temperature storage (0°C to5°C) reduced therespiration rate, maintained a significantly lower relative conductivity and weight loss rate,improved the antioxidant activity of pomegranate arils and exhibited higher total solublesolids and anthocyanins when compared with those stored at10°C and room temperature,which well preserved the quality of pomegranate arils and extended the self-life greatly. Theresults indicated that Storage at0°C led to the best quality preservation.The thickness of PE bags showed little influence on pH, color index and anthocyaninscontent of pomegranate arils. Arils in0.05mm PE bags showed better sensory quality withhigher total soluble solids content, higher antioxidant activity and total phenols at the end ofstorage. The increase of relative conductivity and accumulation of MDA were retarded.Proper heat treatments were effective in increasing pH, SSC and soluble protein contentof fresh arils. It also reduced the weight loss, restrained the decline of antioxidativecompounds (total phenols and anthocyanins) and antioxidant activity, and enhanced theactivity of SOD enzyme. Heat treatments inhibited moulds and yeast count effectively andmaintained a better pomegranate sensory quality. The best overall results were obtained fortreatment at50℃for4min.No significant influence was found on quality parameter or microbial growth of UV-Ctreated arils. However, a promotion in the accumulation of MDA was observed in all UV-Ctreatments, which indicated a damage of the cell wall. Therefore, the use of UV-C seems to be not suitable for keeping quality of ready-to-eat pomegranate arils.