Cereal Chem 63:479-484   |  VIEW ARTICLE
Texture (Hardness and Softness) Variation Among Individual Soft and Hard Wheat Kernels.

C. S. Gaines. Copyright 1986 by the American Association of Cereal Chemists, Inc. 

The texture of individual kernels of soft and hard wheat cultivars was measured by grinding individual kernels in ethanol in a blender jar and subsequently determining median particle size by laser light scattering. This method parallels the production and measurement of break-flour yield of bulk wheat samples. There was a large variation in individual kernel texture within a cultivar (approximately one-half of the texture range of all kernels of the respective wheat class). Most variation in kernel texture of a particular cultivar was observed among the kernels of a single wheat rachis (head), probably resulting from different maturation times of kernels on a wheat rachis. The influence of kernel weight, and indirectly, size, on the measurement of kernel texture was small enough to allow good separation of soft and hard wheat texture data. Estimates of the kernel texture/weight relationship were sufficiently precise to reduce the overlapping of soft and hard wheat data from 6% without consideration of kernel weight to 1.5% when weight was included in the regression. Many hundreds or thousands of kernels were required to statistically differentiate between two samples containing mixtures of hard and soft wheat kernels that have mixture ratios as close as 2%. Overlapping of soft and hard wheat data greatly increases the number of kernels required but is a consequence of a single-kernel method that has a strong relationship with kernel weight, size, and density. If these factors are considered by least squares regression, overlapping may be reduced.