U.S. Department of Agriculture (USDA) scientists have developed a starch-based coating that improves biodegradability and water resistance in products like paper and plastic films. While 100 percent biodegradable, starch lacks the flexibility necessary for many plastic and coating applications. Polyvinyl alcohol (PVOH), a synthetic polymer, is usually used in films and coatings to provide flexibility. However, it has limited biodegradability. …