EFFECT OF SAMPLE VOLUME ON THE COMPRESSIVE FORCE-DEFORMATION CURVES OF CORN FLARES TESTED IN BULK

Two national brands of corn flakes were compressed in cells of various dimensions (height 38-76 mm and diameter 50-91 mm) using a Universal Testing Machine. The stress-strain (sigma vs. epsilon) relationships could be described by a four parameter model originally developed for cellular materials, i.e., sigma(epsilon) = k(1) epsilon(n)1 + k(2) epsilon(n)2 where the k's and n's are constants (n(1) < 1, n(2) > 1). The scatter around the fitted relationships was normalized and its jaggedness determined in terms of an apparent fractal dimension and the mean magnitude of the power spectrum after filtering., The magnitude of both depended on the cell diameter and height indicating that the observed degree of jaggedness is influenced simultaneously by ''averaging'' and ''cushioning'' effects.