Determination of total dietary fiber of intact cereal food products by near-infrared reflectance

Near-infrared reflectance spectra of cereal food products were acquired wit h a commercial dual-diode-array (Si, InGaAs) spectrometer customized to all ow rapid acquisition of scans of intact breakfast cereals, snack foods, who le grains, and milled products. Substantial gains in the performance of mul tivariate calibration models generated from these data were obtained by a c omputational strategy that systematically analyzed the performance of vario us spectral windows. The calibration model based on 137 cereal food product s determined the total dietary fiber (TDF) content of a test set of 45 inta ct diverse cereal food products with root-mean-squared error of cross-valid ation of between 1.8 and 2.0% TDF, relative to the laborious enzymatic-grav imetric reference method. The calibration performance is adequate to estima te TDF over the range of values found in diverse types of cereal food produ cts (0.7-50.1%). The method requires no sample preparation and is relativel y unaffected by specimen moisture content.