Study On Enzymatic Hydrolysis Technology Of Silver Carp Muscle And Characteristics Of Hydrolysate

The proportion of fish protein inside the well-balanced amino acid,high content of essential amino acids,easy digestion and absorption,and has many features.In this study, the flesh of silver carp fish was used as the material,four kinds of enzyme:AS1.398, Alcalase,Flavourzyme and Protamex,that different from sources and the site for hydrolysis,were used for the hydrolysis of muscle.The effects of pretreatment of fish protein on the hydrolysis,the optimum parameters of hydrolysis,the relationship between hydrolysis degree and functional properties of product,and the effects of a variety of conditions on the solubility were studied in the present paper.Based on the high productivity,so that the product has good solubility and functional properties in different conditions of solution.Research results are as follows:1.Pretreatment affected the hydrolysis of Silver carp.Muscle treated by heating or frozen resulted in lower degree of hydrolysis(DH) and recovery ratio of nitrogen than that of fresh one.Heated to 100℃of the fish,the degree of hydrolysis and nitrogen utilization of the minimum.2.Using four types of protease hydrolysis,the best process parameters as follows: AS1.398:initial pH7,proteases dosage is 3600U/g_(protein),55℃,the ratio of materials to water is 1:4;Alcalase:initial pH8.5,proteases dosage is 2400U/g_(protein),50℃,the ratio of materials to water is 1:5;Flavourzyme:pH6,2400U/g_(protein),55℃,and 1:5;Protamex: pH7.5,2400U/g_(protein),55℃,and1:5.Use Alcalase and Flavorzyme for the hydrolysis: with 1800U/g_(protein) Alcalase at the ratio of materials to water of 1:4,initial pH8.0 for 2 hours at 55℃,and then with 1800U/g_(protein) Flavorzyme for another 2 hours,and then, the degree of hydrolysis and nitrogen utilization is better than use any kind of four enzymes.3.Hydrolysis degree and solubility of enzyme hydrolysis products are increasing as the hydrolysis time going.Hydrolysis degree is keeping high in most of pH considerations,more than 95%,except slightly lower at pH6.Hydrolysis degree has great influence on the emulsifying properties,foaming and viscosity properties of the product. Emulsification reaches the highest value 104 when hydrolysis degree goes to 39.10%, there will be better foaming but poorer foam stability by increasing the hydrolysis degree. Viscosity reach the max value 48(mPa.s) when hydrolysis degree goes to 35.78%.4.Solubility of the product can be promoted by low concentration of NaCl. Temperature has little influence on hydrolysis degree,while the isoelectric point can cause the biggest influence on it.However,the products maintain the a higher solubility during this experiment,more than 95%,which is considered to be a fish protein hydrolysis products with soluble good solubility at pH2.0-9.0.