Evaluation of the preservation effect of gelatin-water soluble chitosan film incorporated with maillard peptides on bluefin tuna (Thunnus thynnus) slices packaging
Abstract A new biofilm, consisting of gelatin and water soluble chitosan (carboxymethyl chitosan) and infused with 0.5 mg/mL squid Maillard peptides (F-SMP), was tested as preservative for bluefin tuna stored at 4 ± 1 °C for 10 days. Unwrapped samples were used as control, along with samples wrapped in polyethylene and gelatin-water soluble chitosan films without squid Maillard peptides. Weight loss was observed in all samples, as well as increased hardness, total plate count, total volatile basic nitrogen, peroxide value, and thiobarbituric acid index. The histamine, tyramine and cadaverine concentration in tuna slices increased during storage. In the F-SMP group the concentrations were lower than the other three groups, which were consistent with the total plate count results and suggest that low total plate count could reduce production of biogenic amines. Based on redness, metmyoglobin content, appearance, and sensory evaluation, tuna slices wrapped in F-SMP were the best preserved, with a shelf life of 8 days but only 2–4 days for other samples. The data suggest that the F-SMP effectively inhibit microbial growth and lipid oxidation, and efficiently preserve tuna slices.