THE SIGNIFICANCE OF FIBRILS PRODUCED BY HYDRATION OF WHEAT PROTEINS

Some characteristics of the microscopic protein fibrils generated spontaneously on contact between wheat endosperm particles and a water/air interface have been studied. An inverse relationship between particle concentration and the proportion of particles producing fibrils was discovered. In further experiments, in which particle concentration was carefully controlled, it was found that increase in surface pressure of the suspending medium led to proportionally fewer particles forming fibrils. No evidence was found for the involvement of spontaneously formed fibrils in the floc formation involved in sedimentation tests for flour quality. Surface pressure measurements confirmed the presence of one or more surfactants in flour, and a hypothesis is presented to account for spontaneous fibril formation. Surfactants may be important in determining dough properties but it is unlikely that their influence is mediated through spontaneous fibril formation as few would occur at the high concentrations of endosperm present in dough. © 1990, Academic Press Limited. All rights reserved.