壳聚糖-大豆蛋白-百里香酚乳液制备及其对大口黑鲈保鲜效果OACHSSCDCSTPCD

[Objective]The aim of this study is to prepare chitosan + soy protein + thymol emulsion and investigate its effect on largemouth bass(Micropterus salmoides)fressness preservation.[Methods]Using chitosan(CS),soy protein(SPI)and thymol(Thy)as raw materials,chitosan-soy protein-thymol emulsion(CS-SPI-Thy)were prepared by controlling soy protein concentrations(1.6%,2.4%,3.2%,4.0%,4.8%),and the changes in structure,emulsification capacity and emulsion stability were studied.The perch meat pieces treated with the optimal ratio of emulsion and the untreated were stored at 10℃,and the pH,volatile alkaline nitrogen and total colony count of the fish meat were tested to verify the freshness preservation effect during the storage process.[Results]The emulsion stability index(ESI)and emulsification activity index(EAI)reached the maximum values of(0.92±0.18)%and(8.85±0.13)m2/g,respectively,when the mass fraction of soybean protein was 3.2%;at this time,the particle size was smaller,(13.05±0.05)μm and the zeta-potential was higher(39.64±0.83)mV;At the concentration of 3.2%,the surface hydrophobicity index was the largest,the Maillard reactant generation index was the highest,the endogenous fluorescence intensity was the largest,and the emulsion stability index was the best.The results of pH,volatile base nitrogen and total colony count of the emulsion-treated fish were much better than those of the control group,and the fish meat can be stored for 20 d at the shelf-life temperature of 10℃.[Conclusion]The chitosan + soy protein + thymol emulsion had the best performance when the mass fraction of soybean protein was 3.2%,and the perch meat treated under this condition could be stored for 20 d at 10℃.