Studies On Processing Technology And Correlative Properties Of Silver Carp (Hypophthalmichthys Molitrix Surimi)

Silver carp (Hypophthalmichthys molitrix) is vailable in adequate quantities and has a low commercial value in China, which is processed into surimi and surimi products in order to enhance its added value. This paper mainly studied that effect of washing conditions, adding cryoprotectant chopping conditions microbial transglutaminase (MTGase) on properties of surimi gels in order to provide theoretical support for deep processing and further research.By the different washing conditions, the changes before and after washing, chemical composition, recovery rate of total solids, gel strength, water holding capacity, pH, color, water extractable protein and salt extractable protein, was studied. After making water washing experienment, salt-water washing experienment and washing temperature experienment, the orthogonal experiment was designed. The optimum conditions were obtained by the following condtions:water washing for twice, salt-water washing for once and washing temperature for 13℃.On the basis of predecessors'experiments, the traditional commercial cryoprotectants, sucrose and sorbitol, were selected to research the effect of frozen storage on surimi. The results showed that both sucrose and sorbitol had an obvious effect on preventing the protein denaturation.The results showed that sucrose of 0.8% and sorbitol of 5-8 had better cryoprotective effect.In this paper, using fresh surimi and frozen surimi as raw materials, we studied the effect of initial chopping temperature and salt content on physical properties of surimi including gel strength, water-holding capacity, folding test and color. Collectively, the appropriate initial chopping temperature of surimi was 5-15℃. As the moisture content of frozen surimi was lower than that of fresh surmi, the amount of adding salt can reduce about 0.4%;In addition, in order to improve the gel-formability of the sliver carp surimi, microbial transglutaminase (MTGase) was applied to the surimi gels. According to parameters, gel strength and water capacity, orthogonal experiment was designed. The optimum conditions were suggested to be MTGase of 0.5% at 39℃for 1 h. And then, the surimi gels were analyzed by scanning electron microscopy and SDS-PAGE to study protein molecular and microstructural transformation.