Extraction And Structural Characterization Of Collagen From Pig Skin

With the rapid development of China's economy,people's consumption level is increasing day by day,and the annual consumption of pork is also increasing year by year,but the problem that comes after slaughtering pork will produce a lot of by-products,and pig skin is one of them.Pigskin accounts for about 10% of pig carcasses,but as a by-product of slaughtering,it has not received enough attention.Most companies will directly discard or sell pigskin to leather companies.The pigskin in this article is provided by Foshan Huangyongshun Food Co.,Ltd.The company uses local pig breeding and pork sales as the main profit-making means,but there is no reasonable application for pigskin.Pigskin has a protein content of up to 33%,of which about 87.7% is collagen.Collagen has good physical properties and biological characteristics,and is widely used in food,chemical,biological materials and other industries.Therefore,extracting collagen from pig skin and optimizing its extraction rate have far-reaching significance for increasing the economic value of pig skin resources.In this paper,pig skin is used as the raw material to explore the extraction rate of collagen in two methods of acid leaching and enzymatic hydrolysis,and the process conditions of the two methods are optimized through orthogonal experiments,respectively,and the structural characteristics of the collagen prepared under the optimized conditions are finally characterized..The main contents are as follows:(1)Using pigskin as raw material,the collagen extraction rate is an index.By comparing the extraction rates of porcine skin collagen of hydrochloric acid,acetic acid,citric acid,and lactic acid,it was determined that citric acid had the highest collagen extraction rate among the four;then,for the citric acid,two single-factor optimization experiments including material-liquid ratio and acid leaching time were carried out,and finally through the design of three-factor three-level orthogonal test to confirm that the acid extraction process of collagen in pig skin is p H = 2.4 citric acid,according to the ratio of 1:50(w / v),Soak for 48 hours.(2)Using pigskin as raw material,the index of collagen extraction rate.Through comparative screening of the extraction rates of pepsin,papain and trypsin from pigskin collagen,it is determined that pepsin has the highest collagen extraction rate among the three;further development of pepsin includes enzyme dosage,enzymolysis time,temperature,Five single-factor optimization experiments of material-liquid ratio and p H,and finally through the design of the five-factor three-level orthogonal test to confirm the process conditions of enzymatic hydrolysis method for extracting collagen from pig skin: p H2.0,enzyme dosage 3%,feed liquid Ratio 1:40(w / v),temperature 42 ?,enzymolysis time 8 hours.(3)The three analytical methods of differential calorimetry,ultraviolet spectroscopy,and infrared spectroscopy were used to verify that the product obtained after the pig skin was treated with acid and enzymatic hydrolysis was collagen.In addition,through characterization experiments,it was found that the collagen extracted by the acid method has a more complete structure and stronger thermal stability,but the content of collagen in the product prepared by the enzymatic hydrolysis method is higher.