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Development of standard procedures for a simple, rapid test to determine wheat color class. M. S.
RAM (1), Floyd Dowell (2), Larry Seitz (2), George Lookhart (2), Joe Martin (3), and Dave Funk (4). (1)
Department of Grain Science and Industry, Kansas State University, Manhattan, KS 66506; (2) USDA,
ARS, Grain Marketing and Production Research Center, Manhattan, KS, 66502; (3) Kansas State
University, Hays, KS; (4) FGIS Technical Center, Kansas City, MO.
Red and white wheat cannot be differentiated many times by visual
examination only. Soaking wheat kernels in NaOH solution causes the difference in color to be enhanced.
Red wheat turns a darker red and white wheat turns straw yellow upon soaking in NaOH solution. An
optimum test procedure for color class at field locations has been obtained. The effects of soaking time,
NaOH concentration, temperature, solvents and other bases were determined using a spectrometer and
multivariate analysis (PCA and PLS) of spectral data for several varieties of wheat. The NaOH extracts
from both wheat color classes contained phenolic acids and were similar by UV-Vis, thin-layer
chromatography, and HPLC. Only minor differences were noted in FTIR and Raman spectra of red and
white wheat.
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