Publication no. C-2002-0802-03R |  VIEW ARTICLE

Biochemical Studies of Proteins in Nondeveloped, Partially Developed, and Developed Doughs.

L. Lee (1), P. K. W. Ng (1,2), and J. F. Steffe (1). (1) Department of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824. (2) Corresponding author. Phone: 517-355-8474 (ext. 111). Fax: 517-353-8963. E-mail: <ngp@msu.edu> Cereal Chem. 79(5):654-661. Accepted March 15, 2002. Copyright 2002 American Association of Cereal Chemists, Inc.

Nondeveloped, partially developed with shear and extensional deformations, and developed doughs represent different stages of dough development. To understand the relationship between gluten proteins and dough rheology, this study used disulfide-sulfhydryl analyses, gel filtration chromatography, SDS-PAGE, acid polyacrylamide gel electrophoresis (A-PAGE), and densitometry to examine proteins in the four types of doughs mentioned. Free sulfhydryl content was the lowest in native flour and nondeveloped dough, and the highest in partially developed doughs, while a reverse trend was observed for disulfide content. For each flour sample, the protein elution profile from gel filtration chromatography shifted with the level of dough development. With respect to the smallest sized molecules, native flour had the most, followed by nondeveloped, partially developed, and then developed doughs. SDS-PAGE and A-PAGE exhibited similar protein patterns among the same chromatographed protein fractions of each native flour and its different doughs. Densitometric data showed that the amount of high molecular weight (HMW) glutenins increased and the amounts of low molecular weight (LMW) glutenins, gliadins, and albumins/globulins decreased with progressive stages of dough development. In conjunction with previously published results, indications are that the increase in the size and the amount of HMW glutenins is related to the strength of dough and the amount of protein matrix present in the dough.