30D-16 |
Modification of vital wheat gluten using hydrothermal processing |
Y. Kim1, H. SINGH2, T. J. Herald3, F. MacRitchie2, and R. Madl4. (1) Biological and Agricultural Engineering, Kansas State University, Seaton #141, Manhattan, KS 66506, (2) Grain Science and Industry, Kansas State University, Shellenberger Hall, Manhattan, KS 66506, (3) Animal Science and Industry, Kansas State University, Call Hall 220, Manhattan, KS 66506, (4) Wheat Research Center, Kansas State University, 107 D Waters Hall, Manhattan, KS 66502 Wheat gluten, a co-product of dry and wet milling of wheat, is used almost exclusively as a protein source in the food and feed industries. However, because of high competition from European wheat gluten industry and proteins from other sources such as soybean and egg, its price has fallen below the cost of production in U.S. A short as well as long term solution is to produce better and higher valued products, using either hydrothermal, chemical, or enzymatical process to modify the gluten. The objectives of this study were to investigate the procedure of hydrothermal modification and effect on functionality of the modified commercially available vital wheat gluten (VWG). Two processing parameters for hydrothermal modification were processing temperature (275 and 300oF) and residence time (34 and 92s). The functionalities of modified gluten tested were viscosity, molecular profile and solubility using HPLC. A slurry was prepared by dispersing VGW (Midwest Grain Products Inc., Atchison, KS) in distilled water and lactic acid to form 10% (w/v) concentration. The minimum amount of lactic acid (0.3% v/v) was added to help better dispersing of gluten. The slurries were hydrothermally modified using a jet cooking system (JSC) with different processing parameters of temperature and residence time. Processed slurries were immediately cooled to 100oF and dried with a spray dryer. Among four possible combinations of processing parameters, the lower temperature (275 oF ) and shorter residence time (32s) produced the most favorable results. The viscosity at those settings was the highest (36.2 mPa-s at shear rate at 2 s-1) while that of control sample was 2.2 mPa-s. The highest ratio of polymeric to monomeric fraction and relative total solubility (AU) was also observed from the sample processed at those conditions.
Session 30D, Food Engineering: Physical and chemical properties
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