86 Evaluation of robustness of a 3-year NIRS predictive calibration for oil % and fatty acids concentration in oats.

P. G. KRISHNAN (1), D. L. Reeves (2), K. D. Kephart (2), N. Thiex (3), and M. Calimente (1). (1) Department of Nutrition, Food Science, and Hospitality, (2) Department of Plant Science, and (3) Department of Chemistry, South Dakota State University, Brookings, SD 57007.

Oat oil has a unique fatty acid (FA) profile as it contains oleic and linoleic acids occurring in approximately equal proportions. The oil is distributed throughout the groat and not just in the germ. In addition to a desirable FA profile, it is also a carrier of natural antioxidants such as tocopherols, tocotrienols, ferulic and caffeic acids. There is an increasing interest in exploring oat as a source of edible oil. Environmental and varietal effects on FA variability are of interest to breeders and processors. NIRS was pursued both as a screening and an analytical tool. A third year (1997) was included in the calibrations for oil and fatty acids (expressed as percent of dry matter). All samples were used in calibration development (n = 234). Therefore, 2 sets of data are available for comparisons (reference and NIRS estimate) per constituent. A subsampling including varieties grown in the same locations over the 3 year period permitted ranking of varieties and locations using both methods. No difference was noted between methods. The oat population showed a wide range of oil content (3.98 to 11.7) and a mean of 7.28 percent. The subset range of oil, palmitic, oleic, and linoleic acids was 6.18–8.98, 0.95–1.35, 2.22–3.66, and 2.47–3.51, respectively. Cultivar was the singular factor affecting oil and FA variability. Cultivars Don, Valley Newdak, Hytest, Troy, Jerry, and Settler were ranked high to low in that order for all constituents regardless of the method. Predictive equations yielded strong R-squared and low SEC for oil (0.98, 0.18), palmitic (0.95, 0.04), oleic (0.98, 0.08), and linoleic acids (0.92, 0.09).