Cereal Chem 66:33-38   |  VIEW ARTICLE

Physical Analysis of Isolated Gluten Model Systems Heated in an Experimental Conventional- Microwave Oven.

C. A. LePage, J. Gordon, and E. A. Davis. Copyright 1989 by the American Association of Cereal Chemists, Inc. 

Water loss rates and temperature profiles for isolated gluten model systems heated by conventional and microwave methods were determined before and after hexane extraction of gluten powder. Lipid contents, phosphorus, and sulfur contents were determined. Surface phosphorus-to-sulfur (P:S) and osmium-to-sulfur (Os:S) ratios were determined by energy dispersive X-ray microanalysis. Wide-angle X-ray diffraction was also determined for nonhexane-extracted and hexane-extracted powders. Free and bound lipids, Os:S rations, and P:S ratios (used as an index of surface lipid and phospholipid content) were not changed by extraction. Wide-angle X-ray diffraction showed major peaks between 4.39 and 4.54 angstroms and 9.01 and 9.10 angstroms that were not changed by extraction. Water loss rates for rehydrated gluten samples heated at 200 C showed a local maximum as surface temperatures approached 100 C, followed by increasing rates of water loss as internal temperatures stabilized at 100 C. The local water loss rate maximum was absent in samples heated by microwave radiation, and water loss rates increased until a constant or falling rate period was reached. Surface temperatures and internal temperatures increased at similar rates and stabilized at 100 C. These patterns were similar for both nonhexane-extracted and hexane- extracted glutens.