Effect of packaging on phenols, flavonoids and antioxidant characteristics of mechanical cabinet dried wild pomegranate (Punica granatum L.) arils

Abstract

Wild pomegranate (Punica granatum L.) fruit arils with high acid content are processed into dried arils (anardana) which is used as an ingredient in various medicinal formulations and culinary preparations. The various phenols and flavonoids are responsible for the antioxidant activity of anardana which signifies its functional benefits. The advanced packaging techniques like vacuum packaging, can retain higher antioxidant activity characteristics during storage. So, the present studies were carried out to compare the effect of packaging on total phenols, flavonoids, DPPH (2, 2-diphenyl-1-picrylhydrazyl) antioxidant activity, metal chelating activity, FRAP (ferric reducing antioxidant power) and reducing power of anardana prepared in mechanical cabinet drier. Anardana was packed in different packaging materials and stored under ambient and refrigerated temperature conditions. The overall effect of storage during 12 months revealed that there was a significant (p< 0.05) decrease in total phenols (180.95 to 161.76 mg GAE/100 g), flavonoids (40.60 to 32.66 mg QuE/100 g), DPPH antioxidant activity (61.23 to 56.13%), metal chelating activity (22.25 to 19.37%), FRAP (34.60 to 31.73 ?M Fe2+/100 g) and reducing power (0.610 to 0.521) which was observed less in anardana packed in ALPV (aluminium laminated pouches with vacuum) followed by ALP (aluminium laminated pouches) and gunny bags. Due to slower rates of degradation of various antioxidant compounds, the changes after 12 months of storage were lower under refrigerated conditions. The total phenols, flavonoids and DPPH antioxidant activity were reduced from 180.95 to 167.24 and 156.28 mg GAE/100 g, 40.60 to 34.95 and 30.37 mg QuE/100 g and 61.23 to 57.99 and 54.27 % in refrigerated and ambient temperature conditions, respectively.