The Properties Of Whey Protein Film Modified By Transglutaminase And Oligochitosan

Whey proteins is the by-products in industrial production,it can be bring economic development and environmental benefits.Whey protein and polysaccharide compound,can improve the properties of whey protein film.This subject based on the mechanism of TGase,to study whey protein film-forming properties.It provides a certain theoretical base and practical experience in study of the edible film.This thesis mainly studies the results are as follows:1.Under the condition of carboxymethyl chitosan exist,modification TGase research on whey protein.Electrophoretic analysis showed that crosslinking of whey protein and carboxymethyl chitosan witn TGase.Infrared spectroscopy confirmed that TGase could promote carboxymethyl chitosan crosslinking with whey protein.2.The preparation of whey protein concentrate-carboxymethyl chitosan composite film,to studies at different substrate ratio,glycerol concentration and affect the amount of TGase added to the composite nature of the film.The mainly research of the tensile strength,elongation at break,transparency,solubility and water vapor permeability of composite film,etc.It was found that glycerol concentration of 4%(w/v)WPC-CMC [75:25] composite film was the best.Different substrate ratio films experiment show that compared with the single whey protein,added CMC can improve the tensile strength,elongation at break,transparency,solubility and water vapor permeability of the film;edible film denaturation temperature decreased slightly;the surface of the composite membrane.with CMC content increases gradually smooth.Add TGase can also improve the tensile strength,elongation at break,transparency,solubility and water vapor permeability of the same substrate ratio condition of the composite film;increased the denaturation temperature,WPC-CMC blend film surface morphology and TGase crosslinked WPC-CMC composite membrane was not significantly different.Preparation best overall performance of the composite film was found when the amount of TGase added 4U/g protein,the integrated nature of the composite film is best.3.Preparation of suitable conditions WPC-CMC composite film and single whey protein film.Cover film packaging and coated film packaging for cherry tomatoes and strawberriy,they can effectively reduce soluble solids content and vitamin C content decreased.Composite membranes compared to whey protein film preservation better.After 7 days of storage,composite membrane material package quality whey protein relative stability of the membrane material package better.This study provided theoretical basis for transglutaminase crosslinked modified whey protein,and also enriched the theory of composite edible film,providing an important reference for edible composite film applications in the food sector.