Quality enhancement in fresh and frozen lingcod (Ophiodon elongates) fillets by employment of fish oil incorporated chitosan coatings

Abstract

Abstract The 3% chitosan solutions incorporating 10% fish oil (w/w chitosan, containing 91.2% EPA and DHA) with or without the addition of 0.8% vitamin E were prepared. Fresh lingcod ( Ophiodon elongates ) fillets were vacuum-impregnated in coating solution at 100 mm Hg for 10 min followed by atmospheric restoration for 15 min, dried, and then stored at 2 °C or −20 °C for 3-weeks and 3-months, respectively, for physicochemical and microbial quality evaluation. Chitosan–fish oil coating increased total lipid and omega-3 fatty acid contents of fish by about 3-fold, reduced TBARS values in both fresh and frozen samples, and also decreased drip loss of frozen samples by 14.1–27.6%. Chitosan coatings resulted in 0.37–1.19 and 0.27–1.55 log CFU/g reductions in total plate and psychrotrophic counts in cold stored and frozen stored samples, respectively. Chitosan–fish oil coatings may be used to extend shelf-life and fortify omega-3 fatty acid in lean fish.