CONVERSION OF FOOD INDUSTRIAL-WASTES INTO BIOPLASTICS

The usage of plastics in packaging and disposable products, and the ge neration of plastic waste, have been increasing drastically. Broader u sage of biodegradable plastics in packaging and disposable products as a solution to environmental problems would heavily depend on further reduction of costs and the discovery of novel biodegradable plastics w ith improved properties. In the authors' laboratories, various carbohy drates in the growth media, including sucrose, lactic acid, butyric ac id, valeric acid, and various combinations of butyric and valeric acid s, were utilized as the carbon (c) sources for the production of biopl astics by Alcaligenes eutrophus. As the first step in pursuit Of event ual usage of industrial food wastewater as nutrients for microorganism s to synthesize bioplastics, the authors investigated the usage of mal t wastes from a beer brewery plant as the C sources for the production of bioplastics by microorganisms. Specific polymer production yield b y A. Latus DSM 1124 increased to 70% polymer/cell (g/g) and 32g/L cell dry wt, using malt wastes as the C source. The results of these exper iments indicated that, with the use of different types of food wastes as the C source, different polyhydroxyalkanoate copolymers could be pr oduced with distinct polymer properties.