Effect of chitosan coating and gallic acid on quality properties of common carp (Cyprinus carpio) fillet during storage at refrigerator

The purpose of  this study is to evaluate the oral comparison of chitosan with galic acid Balikiti of typical carp dice films during the preparationof the  refrigeration. Fish fillets were immersed in three groups including 1) control treatment 2) chitosan solution 3) chitosan + gallic acid. Microbial tests including counting aerobic mesophilic bacteria and cryophilic bacteria were performed by purplate method on agar pellet culture medium. Chemical properties including measurement of thiobarbituric acid by spectrophotometry, evaluation of volatile nitrogen compounds by calderal method, free fatty acids by titration method, pH measurement, colorimetric and sensory evaluation of samples by hedonic method were performed by 15 trained evaluators. will be. Comparison of microbial load of aerobic and cryophilic mesophilic bacteria in control sample and different treatments showed that the highest bacterial load related to control sample and mesophilic bacterial load in coated samples were significantly lower than control (P ‹0.05). The amount of bacterial load in the coated samples did not show a significant difference at the end of the storage period (P ‹0.05). Examination of physicochemical factors during the 12-day storage period showed that all coated treatments Significantly (p <0.05) had lower values. The results of sensory evaluation showed that the combination of chitosan and gallic acid can improve the sensory quality of common carp. Overall, the results showed that the use of biopolymers with natural antioxidant and antimicrobial compounds improves the microbiological load, delays oxidative spoilage and increases the shelf life of common carp.