摘要

Chitosan coating is a new preservation technology with good preservation effect and superiority, but has some disadvantages, such as slow speed of film forming, difficulty in the operating and controlling the film thickness. Thus, improving the composition of coating solution and the coating technology is important for its preservation effect. The improved preservative and antibacterial effects on refrigerated grass carp meat was investigated by using new coating method with adding volatile ethanol. By varying the concentrations of ethanol and chitosan in coating solution, as well as coating methods, the total bacteria colony and TVB-N of the fish during its cold storage were studied. The results showed that the coating solution containing 75% ethanol had better antimicrobial and bactericidal effects with a decrease of >51% in initial bacterial count of fresh fish meat. The best chitosan concentration was 1.0% comprehensively considering its film-forming ability and antibacterial effect. In addition, the coating methods showed little difference in affecting the preservation of Grass carp, while spray coating pattern was relatively convenient in operation and economical in coating solution. These findings demonstrated that spray coating using acidic chitosan solution containing 75% ethanol was an effectively new fish preservation technology.

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