Submitted to: Industrie Alimentari
Publication Type: Peer reviewed journal
Publication Acceptance Date: 12/30/2002
Publication Date: 12/30/2002
Citation: Senesi, E., Mc Hugh, T.H. 2002. Film e coperture eduli con matrici a base di frutta. Industrie Alimentari. Anno 41, p. 1289-1294. Interpretive Summary: This research focused on developing new edible and biodegradable packaging materials to store foods and extend their shelf life. These products offer environmental advantages over synthetic packaging materials. Whey protein isolate or soy protein isolate was added to pear puree to form these films. It is important to fruit growers and the dairy and soy industries to find new uses for fruit purees and whey proteins. A new technology, called thermal compression molding, was used to form the films. Functional flexible films were produced using temperatures between 30 and 62 degrees C and pressures between 117 and 324MPa. The strength of these films was measured. These films could be used to form pouches to store dry ingredients, as casings for sausages or vegetarian foods, as films to cover leftovers or in edible ice cream cups and cones.
Technical Abstract: Films based on pear puree were formed using thermal compression molding. Whey protein isolates and soy protein isolates were added to these films to improve their processing and strength. The effects of pear puree concentration, whey or soy protein concentration, moisture content and sorbitol content, as well as molding temperature and pressure, on the final tensile properties of the films were determined. Compression molded films could be formed using 20-60% pear puree, 40-80% whey or soy protein isolate and 0-5% sorbitol. Whey protein containing films were considerably stronger than soy protein containing films. Higher process temperatures resulted in increases in film tensile strength and elastic modulus values. Understanding factors that influence the production of compression molded whey protein films is an important step towards successful extrusion of whey protein films to form edible or biodegradable films or pouches from these materials.