QUALITY EVALUATION OF BARLEY BY NIR SPECTROSCOPY

Authors: Kays, Sandra; Barton Ii, Franklin

Submitted to: US-Japan Coop Pgm on Dev and Util of Natural Products Abstracts Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 11/19/2000
Publication Date: 11/19/2000
Citation: Kays, S.E., Barton II, F.E. 2000. Quality evaluation of barley by nir spectroscopy. United States Japan Cooperative Program in Natural Resources. Proceedings of the 29th Annual Meeting. Abstracts p. 1.

Interpretive Summary:

Technical Abstract: The dietary fiber content of barley can vary widely among cultivars and is a critical quality parameter of cultivars to be used for foods and in the brewing industry. Near-infrared (NIR) spectroscopy was investigated as a screening tool to evaluate the quality of barley, in terms of total dietary fiber and protein contents. Spectra of barley grains from 56 cultivars, grown in Japan, were obtained using a Foss Grainspec.Xact Rice Analyzer (850-1050 nm) and Grainspec A (830-1050 nm) at the National Food Research Institute and of milled barley using an NIRSystems 6500 monochromator (1100-2500 nm) at the USDA-ARS-RRC. Total dietary fiber was determined for each cultivar by the conventional AOAC enzymatic-gravimetric method (Method 991.43) and protein by the AOAC combustion method (Method 992.23). Using multivariate data analysis, models were developed for the prediction of dietary fiber and protein in barley grains and in milled barley. For the prediction of dietary fiber (range 5.3-19.7%) in milled barley samples, second derivative models were developed using partial least squares regression and cross validation. The standard errors of cross-validation (0.53-0.64%) and multiple coefficients of determination (0.94-0.95) indicated a high degree of precision in the prediction of dietary fiber in milled barley using NIR spectroscopy. The development of NIR models for the prediction of total dietary fiber and protein in whole barley grains will be discussed.