Cereal Chem 72:564-567 |
Changes in Solubility and Distribution of Semolina Proteins Due to Extrusion Processing.
P. Ummadi, W. L. Chenoweth, and P. K. W. Ng. Copyright 1995 by the American Association of Cereal Chemists, Inc.
The effects of extrusion processing on wheat protein solubility and molecular weight distribution were investigated. Enriched semolina was extruded using a twin-screw extruder at two different temperatures (50 and 96 C). A modified Osborne fractionation showed a marked decrease in albumin, globulin, gliadin, and glutenin fractions with a concomitant increase in the insoluble residue fraction following extrusion. The effect on protein solubility was greater with the higher extrusion temperature. Sodium dodecyl sulfate polyacrylamide gel electrophoresis patterns of reduced and unreduced protein fractions suggest that conformational changes occurring during extrusion may be responsible for the increase in the insoluble residue fraction.