Abstract
Okara, the waste product of Japanese soy curd industry, was once an important daily food, but modernization in life style has reduced its status. The waste amount is about 677,000 metric ton/year (Amaha et al., 1996). The waste contains high contents of proteins, carbohydrates, and fats. Using the protein isolate of this waste to produce biodegradable films means adding high economic value to it. This may lead to an effective and useful way of using the by-product.HomePage
Compared to soy flour, the protein content in okara is few, and more glycerol amount was needed for the protein isolate to give favorable plasticity to the formed films. Tensile strength at break point, and elongation percentage were smaller than those of a commercial soy protein isolate. However, by adding sodium dodecyl sulfate to the film forming solution, physical properties of the films made with okara protein isolate were improved. It is demonstrated that protein isolated from this waste can be used as a proper material for the production of biodegradable films.Keywords: Biodegradable film, Okara protein isolate, Sodium dodecyl sulfate, Physical properties, Denaturalize