Cereal Chem 52:533 - 548. | VIEW
Changes in Lipid Binding and Distribution During Dough Mixing.
O. K. Chung and C. C. Tsen. Copyright 1975 by the American Association of Cereal Chemists, Inc.
Effects of mixing on lipid binding and distribution were studied by extracting free and bound lipids from wheat flour, lyophilized doughs mixed different times (arrival, peak, departure, and twice the departure time on a farinograph), and various fractions of samples (flour and lyophilized doughs). Samples were fractionated by solubilizing in dilute acetic acid and by centrifugation. Composition of the extracted lipids was studied by thin-layer chromatography and densitometry. Dough mixing affected lipid binding. The initial mixing stage was most critical for lipid binding. Half of flour free lipids (some free nonpolar and all free polar components) became bound when dough was optimally mixed (peak time on a farinograph). Extractability of bound lipid components by water saturated n-butanol depended on their polarities and mixing times. Distribution of proteins and lipids in various fractions was affected by dough mixing. Bound lipid components were distributed differently in sample fractions depending on their polarities. Nonpolar bound lipids were distributed mainly in acetic acid-soluble fractions rich in acid-soluble proteins and highly polar bound lipid components were mainly in acid-insoluble starch-lipid-protein fraction. Lipid components with intermediate polarities became evenly distributed in dough fractions during dough mixing.