Thermal, kinetic, and mechanical properties of glycerol-plasticized wheat gluten.

Glycerol-plasticized wheat gluten was prepared by mixing in an internal mixer equipped with sigma rotors, and then thermally compression-molded to form a sheet for crosslinking and tensile tests. Referring to rubber vulcanization process, rotorless curemeter was applied to test the vulcanization characteristic parameters of the molded round samples, which could be used to calculate the activation energy and reaction rate of crosslinking occurring in wheat gluten when heated. Vulcanizing curves obtained show that the optimum temperature for processing glycerol-plasticized wheat gluten is 150°C, and that activation energy and reaction rate of crosslinking in wheat gluten plasticized with 20 wt % glycerol reach minimum and maximum values, respectively. In addition, glycerol content, plasticizing time, and temperature have significant effects on the mechanical properties of thermomolded wheat gluten plastics. The factors are closely related to the establishment of a covalent network resulting from the formation and rearrangement of disulfide bridges in wheat gluten. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]