Cereal Chem 62:178-184   |  VIEW ARTICLE
Determination of Hardness in Wheat Mixtures. II. Apparatus for Automated Measurement of Hardness of Single Kernels.

F. S. Lai, R. Rousser, D. Brabec, and Y. Pomeranz. Copyright 1985 by the American Association of Cereal Chemists, Inc. 

A continuous automated single-kernel hardness tester (CASK-HaT) was developed to measure stress-strain relations during crushing of single wheat kernels at a rate of 15 kernels per minute. Six parameters, measured from stress-strain curves, permitted determination of hardness of hard and soft red winter wheat varieties from the 1984 crop. The single most important parameter for predicting hardness was the ratio of the first valley to the first peak in the curve. Soft wheats normally had a ratio greater than 0.4 and hard wheats less than 0.3. Computer software was developed for recording, differentiating, and determining composition of mixtures. An experienced operator could distinguish between crushing curves of single kernels of soft and hard wheats from visual observation of a digital oscilloscope. The CASK-HaT, combined with data processing software, was more than 90% accurate in determining compositions of blends of hard and soft red winter wheats.