Cereal Chem. 73 (3):358-363 |
Soft Wheat Products
Relationships of Quantity of Glutenin Subunits of Selected U.S. Soft Wheat Flours to Rheological and Baking Properties.
G. Hou (1), H. Yamamoto (2), and P. K. W. Ng (3). (1) Present address: Wheat Marketing Center, Inc., 1200 N.W. Front Avenue, Suite 230, Portland, OR 97209. (2) Present address: Yamazaki Baking Co., Ltd., 3-15-6, Chitose, Sumida-Ku, Tokyo 130, Japan. (3) Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824. Corresponding author. E-mail: <email@example.com> Accepted February 26, 1996. Copyright 1996 by the American Association of Cereal Chemists, Inc.
The high molecular weight glutenin subunits (HMW-GS) and low molecular weight (LMW) glutenin subunit groups (B and C subunits) in 17 soft wheat patent flours (four wheat classes) and seven straight-grade flours were identified and quantified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) coupled with densitometry using a known quantity of glutenins as a quantitative standard. Flour rheological properties were evaluated and Japanese-type sponge cakes (JSC) and sugar-snap cookies (SSC) were made to evaluate the flours' baking performances. The quantity of B subunits and the ratio of the quantities of B subunits to C subunits were statistically significantly different among four classes of soft wheat patent flours. Patent flours containing subunit 1 showed significantly smaller alveograph P and P/L values and farinograph water absorption values, and larger alveograph L values, larger JSC volumes and bigger SSC diameters than patent flours containing subunit 2*. The quantities of subunits 2*, 6, 8, and 9 were each correlated with some flour rheological and baking properties. The quantity of A subunits had a significantly negative correlation with JSC volume in club wheat patent flours and the quantity of B subunits was strongly associated with larger JSC volume per unit flour protein in western soft white winter (WSWW) wheat flours. The ratio of the quantities of B subunits to C subunits in flour protein may be an important parameter in relation to the SSC diameter for WSWW wheat flours and to the SSC diameter per unit flour protein for club wheat flours. The quantity of total LMW-GS correlated negatively with JSC volume per unit flour protein for eastern soft white winter (ESWW) wheat flours, and the total glutenin subunits associated negatively with SSC diameter per unit flour protein for ESWW wheat flours and with JSC volume for club wheat flours.