Spectroscopic Determination of Chemical Properties of DDGS

Abstract: Samples of distillers dried grains with solubles (DDGS) were obtained by the National Corn-to- Ethanol Research Center (NCERC) from about 40 dry-grind ethanol plants for four different time periods in 2007 and 2008. Laboratory values for crude fat, protein, neutral detergent fiber (NDF), acid detergent fiber (ADF), residual starch and moisture were determined. Samples were scanned in reflectance mode on a Perkin-Elmer Spectrum-One Fourier Transform near-infrared spectrometer (12,000 to 4,000 cm-1). On DDGS calibrations on NCERC data, oven moisture was predicted with an R value of 0.93 and RPD of 2.88. Crude protein, crude fat and residual starch were predicted with R values of 0.87, 0.88, and 0.81, respectively; and with RPD values of 2.0 or above. ADF and NDF had R values of 0.82 and 0.80, respectively; but also higher RMSEP and lower RPD values.