Effect of chitosan coating enriched with orange peel (Citrus sinensis) waste extract on prolonged preservation and chemical and functional properties of frozen beluga sturgeon (Huso huso) fillet

Fish is an important part of the diet in both developed and developing countries. It is highly digestible and contains an appropriate combination of essential amino acids such as lysine and methionine, which are essential for good health and nutrition. The health benefits of essential polyunsaturated fatty acids, including omega-3 and omega-6 fats, have stimulated interest in increasing seafood consumption per capita. However, fresh fish is one of the most perishable foods due to the potent action of autolytic enzymes and microbial activity. In this study, chitosan biofilms containing different concentrations of the orangepeel extract (0.5, 1.0, and 1.5%) were prepared and their physical factors including water vapor permeability (WVP), color, and water solubility (WS) were characterized. Enrichment of the chitosan-based coatings with orange peel extracts improved the physical property factors and WVP, color, and WS improved for prolonged preservation of frozen beluga sturgeon so that significant differences in these factors were observed between the enriched coatings and control ones (p 0.05). The fish fillets were analyzed for total lipid (3.33 ± 0.41%), crude protein (14.90 ± 1.04% ), and total volatile basic nitrogen (10.12 ± 1.15 mg N/100 gr) and then subjected to the three treatments as well as blank coatings with 0.0-1.5% levels of orange peel waste extract for 14 days at 4 ⁰C. The results showed that the biofilm enriched with 1.5% orange peel waste extract was effective in preserving phenolic compounds and maintaining the antioxidant properties of fish fillets during the preservation period (p 0.05). The results of this study showed that the chitosan coating enriched with orange peel extract improved physical factors in the coatings preserved the antioxidant compounds in the fish fillets and maintained their shelf life during a two-week refrigeration period.