Study On The Preparation Of Tilapia Skin Collagen Peptides Chelated With Zinc And Its Properties

The output of Tilapia cultured in our country occupies first place in the world. With the increasing international market demand for Tilapia.This promotes Tilapia processing industry to develop.During the processing,a large number of byproduct was produced.Preparing small molecular weight peptide from Tilapia skin collagen (TSP-â… ) by enzymatic hydrolysis not only has the characteristics of a variety of functions,but also to promote the absorption of zinc.In this thesis,the enzyme technology of Tilapia skin collagen(TSP-â… ) and the using of ultrafiltration technique was discussed,Especially focused on the producing of the high biological zinc chelate from Tilapia skin collagen polypeptide and zinc sulfate.This research was expected to create an economic and effective new approach of utilization of these byproduct.The main content of this research is as the follows:1.This paper studied the optimum hydrolysis conditions of TSP-â… with five single enzymes,and selected the papain.A TSP-â… hydrolysis Kinetic model of papain including the factors of the enzyme concentration,time,temperature,substrate concentration and pH was established with Second Order Regression Designing in SAS analysis system.2.TSP-â… solution was chosen as the ultrafiltration treatment materials on getting the peptides hydrolyzed after 3000Da ultrafiltration(TSP-â…¡).The composition of amino acid and molecular weight distribution were compared.3.TSP-â… and TSP-â…¡chelated with zinc sulfate using water-bath heating method. The chelate condition was studied.The optimum condition was obtained by used Response surface methodology(RSM) to determine optimum chelate condition for chelate ratio.Hot air drying and spray drying was used to produce polypeptide-zinc.4.TSP-â… chelated zinc was rapidly synthesized under microwave radiation in solid state,and the processing condition during the synthesis was studied.5.The Product was confirmed as polypeptide chelated with zinc by chemical characterization and infrared spectrum analysis.The total content of zinc among polypeptide-zinc was determined by flame atomic absorption spectrometry.Different kinds of Zn were added to two kinds of edible oils for storage experiments investigating catalyzing effects of lipid oxidation.