Modified fish skin collagen and preparation method

The invention relates to modified fish skin collagen and a preparation method. The preparation method comprises the following steps of: preparing 6.67 percent aqueous solution from the fish skin collagen in a weight volume ratio of g/ml, then adding glutamine transaminase in an amount which accounts for 2 percent of the weight of the fish skin collagen in the aqueous solution; after dissolving the glutamine transaminase fully, adding 2 percent solution of chitosan acetic acid in the volume ratio of 1-2:1; and homogenizing and performing vacuum degassing, and then heating the mixture at the temperature of between 40 and 50 DEG C for 30 minutes to obtain the modified fish skin collagen solution. The gel strength of the prepared modified fish skin collagen solution is 80 to 90g, modulus of elasticity is 550 to 740MPa at the temperature of 25 DEG C, and modulus of viscosity is 3,160 to 4,230MPa at the temperature of 25 DEG C. In the invention, the fish skin collagen is modified by combining the glutamine transaminase with the chitosan, so that the gel strength of the fish skin collagen solution is intensified, and the defect of low mechanical property is overcome. The modified fish skin collagen has a simple process and good modification effect and can be used for manufacturing packaging films in the fields of food, medicaments and cosmetic.