MECHANICAL-PROPERTIES OF WHEAT

Fundamental mechanical properties of the wheat kernel were characteriz ed for five different wheat classes. An Instron testing machine was us ed to perform a compression test on wheat slices. Wheat slices were pr epared by cutting off both ends of the wheat kernel. A cross-sectional area of the wheat slices was measured using a commercial image proces sing system. An offset yield of 0.2 % was introduced for determining t he yield point for wheat and used to determine yield stress, yield str ain, modulus of deformability, and energy to yield point. To determine the effect of sample location, each kernel of hard red spring and sof t red winter wheats was cut into two slices (germ end and brush end). No significant differences, a = 0.05, were found in values of the phys ical properties for germ-end and brush-end samples. In general, the fo ur properties increased as loading rate increased up to a 100 mm/min a nd decreased thereafter The mean values of yield stress for all five w heat classes decreased as moisture content increased. Soft wheat sampl es had generally lower modulus of deformability values.