The combined use of lysozyme, nisin and chitosan for the preservation of iced pomfret

On the base of the research of single biological preservative, the orthogonal experiment was made to investigate the fresh-keeping effect of complex biological preservatives (a miture of lysozyme, nisin and chitosan) in the preservation of pomfret under the cold storage. The total bacterial count, TVB-N were used to evaluate its quality. According to the results of orthogonal experiment L9 (33) , the best concentrations of lysozyme, chitosan, and Nisin were as follows 0.4, 5, 0.4g/L. The sensory scores, total bacterial count, TVB-N and TBA of pomfret treated by the complex biological preservatives were better than uncoated one. The first grade freshness of pomfret treated by the complex biological preservatives could be extended 2 ³ days, and the two grade freshness could be extended 6⁷ days.