Method for preparing tilapia fishskin small molecular peptide chelate zinc salt

[0039] Implementation case:

[0040] Weigh 100.0008g of clean tilapia skins, immerse them in 700ml of 0.1mol/L hydrochloric acid solution and 0.1mol/L sodium hydroxide solution for 1hr after degreasing treatment, wash with distilled water to neutrality, and keep at 45℃. Homogenize with 1000ml of distilled water at constant temperature for 12 hours, extract the supernatant by suction filtration, heat up to 50°C-55°C, adjust the pH to 6.0, add 0.04671g papain for constant temperature enzymatic hydrolysis for 2 hours, and then in a water bath at 100°C. After heating for 20 minutes, the enzymatic hydrolysis reaction is terminated, and the fish skin proteolysis solution is obtained. The hydrolysis degree of tilapia fish skin protein is 12.3%.

[0041] A compound decolorant (mixed with 3g/L of activated carbon yeast and cyclodextrin) was used to debitter, decolor and deodorize the fish skin proteolysis solution, and collect the supernatant by centrifugal filtration at 4000 r/min. Pass 001*7(732) cation exchange resin at room temperature at a flow rate of 8 times the column volume/h, collect the effluent, and measure its nitrogen recovery rate of 95.40%. Then the decationized hydrolyzate is 8 times the column volume/ The flow rate of h passes through 201*7 (717) anion exchange resin, and the effluent is collected. The nitrogen recovery rate is 93.31% and the salt rejection rate is 93.15%. After the effluent is concentrated, it is subjected to ultrafiltration. The working pressure of the ultrafiltration equipment is 28 psi, the temperature of the material liquid is 29°C, the pH of the material liquid is 6.7, and the ultrafiltration treatment is 40 minutes to obtain the fish skin polypeptide liquid, namely the TSP-II solution.

[0042] Take the peptide content in the TSP-II solution as an indicator, and adjust the pH of the reaction to 6.0 according to the mass ratio of it to zinc sulfate of 3:1, the water bath at a constant temperature of 60°C, and magnetic stirring for 1hr to obtain the chelate solution. After washing with water and ethanol for 2-3 times, after the solution is subjected to suction filtration, the filter residue is placed in an electric heating constant temperature blast drying oven at a constant temperature of 80 ℃ and dried for 30 minutes to obtain the product II-Zn 2+ , The chelation rate of zinc sulfate was 92.31%, and the chelate yield was 28.39%. II-Zn 2+The particle size measurement results of TSP-II and TSP-II are 9436.2nm and 485.0nm, respectively, the Zeta potential is -0.31mv and -4.36mv, the ratio of raw material and water is 1:5, and the viscosity measured at 25℃ is 3.73cp and 2.33 cp.

[0043] Product feature analysis

[0044] Take TSP-II and II-Zn respectively 2+ For comparative analysis, the analysis results are as follows:

[0045] 1. Color

[0046] TSP-II is white powder, II-Zn 2+ It is light yellow powder.

[0047] 2. Rheology