The Exploitation And Studies Of Edible Composite Protein Packaging Films

Edible packaging film is defined as membrane, which is formed by interacting between different molecules and come from nature and edibe material such as polysaccharide, protein, etc, adding plasticizers and crosslinking agents. Edible packaging film can be eaten together with food packaged with it. So it can' t bring about environment pollution. In recent years, edible packaging film was studied thoroughly by many researchers at home and abroad and gained some positive results. But there aren't system reports at home and abroad about the studies on the exploitation and studies of edible composite protein packaging films. Add great molecule materials or cross-linking reagent to wheat gluten,which is the main material of filming in the paper, to improve the mechanical capability of films ,and then we choose a kind of better great molecule material and confirm its best quantity. Add 5 kinds of different fatty acids to wheat gluten, which is the main material of filming, to improve the obstructive capability, and then we choose a kind of better fatty acid and confirm its best quantity. The main results indicated:1. The main factors that affect the synthetical capability of the wheat gluten films are in sequence: the temperature of heating, pH, the proportion of glycerol and wheat gluten,the volume percentage of ethanol. When the temperature of heating is 80 °C, pH is 10, the proportion of glycerol and wheat gluten is 3:10 and the volume percentage of ethanol is 50%,we can get a better synthetical capability. At the time the rate of light permeation is (22.6±0.35)%, the water-solubility is (32.30±0.55)%, tensile strength is (2.52±0.03)MPa, elongation at break is (277.63±2.76)% and water vapor permeability is (6.185±0.31)X 10^-11g/m*s*Pa.2. The best of the synthetical capability is the film that is constituted by soy protein isolated and wheat gluten in the all of the great molecule materials choosed.Its best adding proportion is 1:4. At the time the rate of light permeation is (25.4±0.65)%, the water-solubility is (33.36±0.28)%, tensile strength is (3.05±0.04)MPa, elongation at break is (247.00±3.92)% and water vapor permeability is (5.424±0.23)X 10^-11g/m*s* Pa.