A RAPID GENERAL-METHOD FOR APPRAISING THE RHEOLOGICAL PROPERTIES OF THE STARCHY ENDOSPERM OF CEREAL-GRAINS

A rapid, simple method was developed to prepare small, parallelepipeda l test samples of endosperm of wheat, corn, and rice grains. Compressi on tests performed on endosperm samples revealed the following mechani cal properties: modulus of elasticity (E, Cpa), breaking stress (sigma (rup), MPa), and maximum breaking strain (epsilon(rup), %). All tests were performed on several endosperm test samples of each cereal specie s. The results displayed good repeatability and several significant di fferences in the mechanical behavior of different endosperm structures , especially among soft, hard, and durum wheats. Rice and corn endospe rm displayed mechanical behavior similar to that of durum wheat endosp erm. The method proposed appears to be sufficiently sensitive and repe atable for studying the incidence of hardness and vitreousness of cere al grain endosperm in relation to its suitability for milling.