Cereal Chem 69:502-507   |  VIEW ARTICLE

Bread Crumb Amylograph Studies. II. Cause of Unique Properties.

A. Xu, J. G. Ponte, Jr., and O. K. Chung. Copyright 1992 by the American Association of Cereal Chemists, Inc. 

Amylograms of bread crumb have a bump in the setback stage and sometimes a minor peak before the major peak in the heating stage. In repeated amylograph cycles, bread flour alone showed a bump in both heating and cooling stages. With repeated heating and cooling cycles, bread crumb also showed a second bump in the heating stage. In a bread crumb amylogram, the minor peak temperature was superimposed on the falling edge of the bump in the second heating period, suggesting that they were caused by similar factors. Wheat starch and wheat flour polar lipids were shown to be responsible for bump formation. Viscosity changes indicated by shapes of the bumps were temperature-dependent. Differential scanning calorimetry showed endothermic and exothermic peaks, respectively, upon repeated heating and cooling. Addition of sodium stearoyl lactylate to wheat starch also caused bumps in the amylogram. Complexing of lipids, mainly polar lipids, with solubilized starch molecules, and crystallization of the complex in the cooling stage, as well as melting of the crystals and dissociation of the complex in the heating stage probably caused the changes in viscosity during bump formation.