Cereal Chem 63:361-364   |  VIEW ARTICLE
Buckwheat Browning and Color Assessment.

G. Mazza. Copyright 1986 by the American Association of Cereal Chemists, Inc. 

A modified procedure for measuring nonenzymatic browning of buckwheat grats was developed. The procedure is based on extraction of soluble colored materials, clarification of the resultant extracts, and spectrophotometric evaluation of the extracted color. Using buckwheat groats subjected to high storage temperatures, browning results obtained by this procedure were compared to surface color of the groats determined with a Hunterlab tristimulus colorimeter. The correlation coefficients between absorbance of the extracted color of 420 nm and CIE tristimulus values, X, Y, and Z, were -0.966, -0.914, and -0.947, and those between absorbance and Hunter L, a, and b values were -0.974,0.970, and -0.901, respectively. When the modified procedure was used to investigate the influence of water activity on nonenzymatic browning of buckwheat groats, it was found that minimum production of pigments occured at water activities corresponding to the monolayer moisture content. The correlations between absorbance of the extracted color and Hunter color values of samples stored at 0.11-0.67 water activities were lower than those obtained with samples subjected to high storage temperatures; however, they were still sufficiently high to be useful for predicting color changes in buckwheat groats and could be used commercially for routine quality- control purposes.