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Thermo-molded wheat gluten plastics: effect of molding temperature, molding time and gluten moisture content on the gluten network Koen J.A. Jansens, Bert Lagrain, Kristof Brijs, Mario Smet and Jan A. Delcour Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe), Katholieke Universiteit Leuven, Kasteelpark Arenberg 20, B-3001 Leuven, Belgium Molecular Design and Synthesis, Katholieke Universiteit Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium Gluten proteins, the storage proteins of wheat, can be converted into a plastic-like material by thermo-molding. Thermal treatment of gluten results in the formation of covalent cross-links, predominantly disulfide bonds, in and between proteins. The aim of the present work was to study the effect of molding temperature (130-170 °C), molding time (5-25 min) and moisture content (5.6-18.0 %) on the gluten network. Molding temperature, molding time and gluten moisture content had a strong impact on the SDS extractable protein (SDS-EP) as determined with size-exclusion HPLC. SDS-EP, and more particularly the gliadin extractability, decreased for gluten molded at 130 °C with increasing molding times and moisture contents. Under the experimental conditions, almost no glutenins were extractable after thermo-molding. At 170 °C, degradation of gluten seems to occur. Reversed-phase HPLC results showed that the α- and γ-gliadins were more affected by thermo-molding than the ω-gliadins. Furthermore, there were indications that other types of cross-links, besides disulfide bonds, become increasingly important at these high temperatures.