Cereal Chem. 73 (5):601-604  |  VIEW ARTICLE

Engineering and Processing

Starch-Based Plastic Foams From Various Starch Sources (1).

S. Bhatnagar (2) and Milford A. Hanna (3). (1) Published as Journal Series No. 11403 of the University of Nebraska, Agricultural Research Division. (2) Research associate, Industrial Agricultural Products Center, University of Nebraska, Lincoln, NE. (3) Professor, Departments of Food Science and Technology and Biological Systems Engineering and Director, Industrial Agricultural Products Center, University of Nebraska, Lincoln, NE 68583-0730. Corresponding author. E-mail: <BSEN024@UNLVM.UNL.EDU> Accepted May 14, 1996. Copyright 1996 by the American Association of Cereal Chemists, Inc. 

Corn, tapioca, wheat, rice, and potato starches were extruded with 30% polystyrene and 5% magnesium silicate or 1% polycarbonate or 0.5% azodicarbonamide in a single screw C. W. Brabender laboratory extruder at 140°C barrel temperature, 140 rpm screw speed, and 16% starch moisture content on dry weight basis. The foams did not show presence of either free starch or polystyrene. The components were well grafted as was confirmed by X-ray diffraction patterns of extrudates and water solubility indexes. The expansion, unit density and water solubility index of the extrudates depended on source of starch and the type of additive. In general, tapioca and corn starches gave the best products with any of the additives.