Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: 4/28/1996
Publication Date: N/A
Technical Abstract: Supcritical fluid chromatography (SFC), utilizing pressure, density, or temperature programming, provides an accelerated analysis method for characterizing many complex lipid mixtures. Utilizing primarily nonpolar SB (Dionex) stationary phases in 50/100 micron i.d. columns, 5-25 m in length, we have separated lipid species according to their molecular weight and polarity, thereby permitting a tenative identification of the lipid solute on the basis of relative retention. Capillary SFC has been applied advantageously to monitor transesterification, glycerolysis, and hydrolysis reactions performed on common vegetable oils and naturally occurring ester and wax mixtures, allowing completion of these reactions to be ascertained. Such information can be obtained within 30 min by using rapid SFC programs and without resorting to extensive sample preparation. Capillary SFC has also proven advantageous in analyzing minor lipid constituents in food and industrial products, such as cholesterol in foods and tocopherols in vegetable oils at 1-50 mg/100 g of sample levels using an FID. This provides a suitable method for determining cholesterol and/or fat soluble vitamins, in neat or extracted samples from analytical SFE, for nutritional labeling purposes. Finally, SFC has proved a valuable diagnostic aid in confirming the effect of supercritical fluid extraction/fractionation processes on lipid-bearing substrates and extracts; e.g., the fractionation of wool grease and evening primrose oil with respect to time.