Cereal Chem 64:177-181   |  VIEW ARTICLE

Qualitative Characterization of the Purity of Milled Durum Wheat Products by Multidimensional Statistical Analysis of Their Mid-Infrared Diffuse Reflectance Spectra.

C. Renard, P. Robert, D. Bertrand, M. F. Devaux, and J. Abecassis. Copyright 1987 by the American Association of Cereal Chemists, Inc. 

Because assessment of durum wheat semolina purity by the standard ash test has been widely criticized, we attempted to characterize products of a semolina mill by mid-infrared diffuse reflectance spectroscopy, which up to now has met with limited success. Recent technological advances may open new possibilities for this spectral range; new mathematical treatments are reported that extract the main spectral phenomena in a set of spectra. A collection of milled wheat products ranging from very pure semolinas to brans was chosen for this study. Three mathematical treatments (multidimensional statistical analyses) were applied to the spectra to condense the data with minimal loss of information: principal component analysis, morphological analysis, and correspondence factorial analysis. By these methods, characteristic wave numbers of the main components of wheat were identified for starch (1,166, 1,102, and 1,066 cm-1), cellulose (1,134 and 1,178 cm-1), noncellulosic cell-wall components (1,730 and 1,594 cm-1), and gluten (1,694 and 1,554 cm-1). Maps showing a separation of the three kinds of milled products (semolinas, flours, and brans) and a rough classification of these products according to purity were obtained without biochemical calibration.