APPLICATION OF CHITOSAN TO MAINTAIN THE QUALITY OF KAMABOKO GELS MADE FROM GRASS CARP (CTENOPHARYNGODON IDELLUS) DURING STORAGE

ABSTRACT Chitosan was added to kamaboko gels made from grass carp (Ctenopharyngodon idellus), and the effects on preservation quality were determined by biochemical (pH, total volatile basic nitrogen [TVBN], thiobarbituric acid [TBA], peroxide value) and microbiological (total bacterial count) determinations during storage at 4C. Application of chitosan, at a level of 1% (w/w), exhibited a beneficial effect on inhibiting lipid oxidation and bacterial growth in the gels. The preservative function was related to the molecular weight of chitosans. Relative low molecular weight chitosan showed a higher antioxidant capacity than high molecular weight chitosan. However, mixture of 300 and 10 kDa chitosans exhibited the highest antibacterial activity. Increases of pH, TVBN, TBA and peroxide values in gels during storage were significantly reduced when chitosan was applied. The present study provides a possible application of chitosan as a food additive for surimi-based foods. PRACTICAL APPLICATIONS Surimi-based product processing is an effective way to utilize freshwater fish with low commercial value, but the shelf life of surimi products is quite limited. Therefore, preservatives are commonly added to surimi products to extend the shelf life. This research has investigated the effect of chitosan, a natural preservative and antioxidant, on maintaining the quality of grass carp gels during storage at 4C. Results showed that chitosan could inhibit the growth of microorganism and prevent lipid oxidation, which was related to the molecular weight of chitosans. The present study should provide a possible application of chitosan as a natural food additive for surimi foods.