Influence of Sorghum Wax, Glycerin, and Sorbitol on Physical Properties of Soy Protein Isolate Films

Authors

Ki Myong Kim, University of Nebraska-Lincoln
David B. Marx, University of Nebraska-LincolnFollow
Curtis Weller, University of Nebraska-LincolnFollow
Milford Hanna, University of Nebraska-LincolnFollow

Date of this Version

1-2003

Comments

Published in Journal of the American Oil Chemists’ Society 80:1 (January 2003), pp. 71–76; paper no. J10202. Copyright © 2003 by AOCS Press. Used by permission.

Abstract

Sorghum wax, sorbitol, glycerin, and soy protein isolate (SPI) composite films were prepared. Effects of sorghum wax, sorbitol, and glycerin concentrations on various films were evaluated using response surface methodology. All independent variables significantly (P < 0.05) affected film water vapor permeability (WVP), tensile strength (TS), elongation at break (E), total color difference, and total soluble matter (TSM). Increasing the sorghum wax concentration decreased WVP and E. As sorbitol content increased in the composite films, WVP and TS increased. Sorbitol had a critical point of 2–5 g/5 g SPI for low values of TSM. The addition of sorbitol contributed more to the properties of the film than did glycerin.