Advances in the Application of Edible Antimicrobial Coatings and Films for Fish Preservation

Fish are widely consumed owing to their high nutritional value. However, preserving fish remains challenging because they are highly susceptible to spoilage. This article reviews the spoilage mechanisms of fish and the recent advances in edible antimicrobial coatings based on chitosan, sodium alginate, gelatin, and pectin for fish preservation. The antimicrobial and antioxidant activities of these biopolymers, as well as their composites, can be greatly enhanced by incorporating natural antimicrobial agents such as plant polyphenols, essential oils, and microbial preservatives, thereby effectively extending fish shelf life. Chitosan is particularly notable for its potent antimicrobial activity and excellent oxygen barrier properties, and calcium-cross-linked sodium alginate systems are valued for their gel-forming ability, mechanical strength, and high loading capacity. Applications of these edible coatings have been shown to significantly improve the quality and shelf life of fish products. Data from studies report that these coatings reduce total viable count by 16.67-70.77%, total volatile basic nitrogen by 28.57-75.78%, and thiobarbituric acid by 25-86.18%, resulting in a shelf life extension of 20-233%. Overall, edible antimicrobial coatings hold great promise in enhancing the preservation of fish products.