728 PB 474 PARTIAL OIL EXTRACTION OF PECAN HALVES BY SUPERCRITICAL FLUID EXTRACTION

Partial oil extraction is being investigated as a means to increase oxidative stability and provide reduced fat pecan halves. Supercritical extraction with carbon dioxide provided a means to extract twenty to thirty percent of resident oil, with little to no kernel damage and leaving no harmful residues in the kernel or the extracted oil. Variances in extraction time, temperature, pressure and total carbon dioxide volume used for extraction with a continuous flow extractor will be discussed. Fatty acid composition of oils extracted using supercritical carbon dioxide was essentially the same as oils obtained by solvent extraction and by cold press. Fatty acid yield in the oils was greater for supercritical extraction compared to the other two methods. Oxidative stability for extracted and unextracted pecans, determined using an accelerated aging technique, will be compared. Supported by USDA grant 92-34150-7190 and the Oklahoma Agricultural Experiment Station.