Properties of phenolic acid-chitosan composite films and preservative effect on Penaeus vannamei

Abstract Five kinds of phenolic acid-chitosan composite films including p-coumaric acid-chitosan, ferulic acid-chitosan, gallic acid-chitosan, vanillic acid-chitosan and salicylic acid-chitosan composite films with same content of phenolic acids were prepared, respectively. Their physical, mechanical and biological properties were investigated. Further, the preservative effect of ferulic acid-chitosan composite films and p-coumaric acid-chitosan composite films on Penaeus vannamei was evaluated. The results indicated that phenolic acids changed physical properties, decreased the mechanical properties, and increased biological properties of chitosan film. Among the phenolic acid-chitosan composite films, gallic acid-chitosan composite films possessed the best physical properties, mechanical properties, antioxidant and antimicrobial activities, which may be related to three phenolic hydroxyl groups in its molecule. In the shrimp preservation experiment, ferulic acid-chitosan composite films showed better preservative effect on shrimps in terms of weight loss, pH value, total volatile basic nitrogen, thiobarbituric acid value, total bacterial count and sensory score of shrimps during storage. The results may be related to the methoxy group in ferulic acid. The work revealed that the properties and preservative effect on shrimp of chitosan film were influenced by structures of phenolic acids.