Effect of Different Packaging Conditions and Packaging Materials on Proximate Composition and pH of Solar-dried Indian Mackerel (Rastrelliger kanagurta) Stored at Room Temperature

Abstract

This study evaluated the effects of packaging conditions and materials on the proximate composition and pH of solar-dried Indian mackerel (Rastrelliger kanagurta) during 180 days of storage at room temperature. Fresh mackerel contained 70.82% moisture, 18.75% protein, 9.45% fat and 1.26% ash, with a pH of 6.7. Following salting and solar drying, samples were packed in gunny bags (control), low-density polyethylene, dotted low-density polyethylene and polyamide/polyethylene pouches under air or vacuum conditions. Moisture, protein, fat, ash and pH were evaluated at 30-day intervals using standard analytical methods. Moisture content and pH increased during storage, whereas protein, fat and ash contents generally decreased. The gunny-bag control exhibited greater changes in the measured characteristics than the vacuum-packaged samples. Among the evaluated treatments, vacuum packaging in polyamide/polyethylene pouches (MVP3) resulted in the lowest final moisture content (23.26%) and pH (6.85). This treatment also retained higher protein, fat and ash contents than the control, with final fat and ash values of 8.42% and 13.68%, respectively. The findings indicate that packaging conditions and materials influenced the physicochemical characteristics of solar-dried Indian mackerel during room-temperature storage. Vacuum packaging in polyamide/polyethylene pouches was the most effective treatment evaluated for limiting changes in the measured parameters over 180 days.