Combined Effect of Polyphenol-Chitosan Coating and Irradiation on the Microbial and Sensory Quality of Carp Fillets

Irradiation can extend the shelf-life of fish, but it may cause unacceptable change on quality. Since rose polyphenols have high antioxidant and antibacterial activities, this study evaluated the combined effect of polyphenol-chitosan coatings and irradiation (3 kGy) on the microbial and sensory qualities of carp fillets during storage at 4 degrees C. A dose of 3 kGy irradiation reduced the initial total viable counts (TVC) and psychrophiles, and increased the initial b(*) and thiobarbituric acid reactive substance (TBARS) values. During storage, TBARS, TVC and psychrophiles of nonirradiated samples increased faster and were higher than those irradiated. Regardless of irradiation treatment, samples coated with chitosan containing rose polyphenols had lower TBARS, pH and bacteria than that in no coating or chitosan coating batches. Carp treated with combined treatment could preserve an acceptable sensory quality at the end of storage. The result indicated that polyphenol-chitosan coating combined with irradiation can maintain fish quality by preventing bacterial growth, oxidation, and changes in color and sensory acceptability. Practical Application A dose of 3 kGy irradiation can effectively reduce bacterial counts in fish, but it causes oxidation and color change. Polyphenol-chitosancoating combined with irradiation can practically inhibit bacterial growth, prevent oxidation, and maintain color and sensory quality during irradiation and chilled storage.