Determining the wetting capacity of the chitosan coatings from Ucides cordatus and evaluating the shelf-life quality of Scomberomorus brasiliensis fillets

Abstract

The aim of this study was to determine the wetting capacity of a new chitosan source (Ucides cordatus (Uçá-crab)) on quality of frozen serra fillets. First, nine coating solutions were produced using three concentrations of chitosan (1.5%, 2.0%, and 2.5%) and three concentrations of glycerol (0.3%, 0.45%, and 0.6%). Then, the spreading coefficient (Ws) of the coating solutions on the surface of serra fillet was determined. Coating with 2.0% chitosan and 0.60% glycerol produced Ws near to zero, with a value of −11.72 ± 4.56 mM/m. This solution was selected and applied to serra fillet, and the shelf-life at −18 °C was evaluated for 180 days. Coating loss (chitosan and water) and weight loss of the serra fillet were analyzed. During storage, the physicochemical parameters of the fillets (pH, total volatile nitrogen bases, trimethylamine nitrogen, thiobarbituric acid reactive substances) and the microbiological profile were analyzed. The results showed that the chitosan coating produced less loss of coating when compared to the glaze. In addition, the chitosan coating extended the life of the serra fillet when compared to both glaze and control groups. This effect was produced due to lower bacterial growth that generated more suitable physicochemical conditions. Uçá-crab showed to be a suitable source for the production of edible chitosan coating with adequate properties to improve the shelf-life of Serra fillet.