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: The fat content of oilseed and meat samples has been determined employing a supercritical fluid extraction (SFE) - supercritical fluid reaction (SFR) - gas chromatography (GC) hyphenated technique. The method utilizes a simultaneous extraction of the fat by supercritical carbon dioxide and an enzyme-catalyzed methylation of the fat prior to GC analysis. This method has been shown to facilitate complete conversion of major fat constituents, e.g., triglycerides, to their respective fatty acid methyl esters (FAME). However, it is uncertain whether constituents, such as phospholipids and cholesterol esters, which are present in small quantities in the above sample matrices, are extracted or reacted using the above technique. In this study, four saturated cholesteryl ester samples (C16:0, C18:0, C17:0, and C20:0) and four phosphatidic acids were analyzed. Conditions for the SFE/SFR step were 50 deg C, 2500 psi, a liquid C02 flow rate of 1mL/min, methanol flow of 0.5mL/min, and extraction/reaction time of 50 min. Recovery and reaction data were determined by GC, TLC, HPLC, and SFC analysis of the extract products. Conversion of the cholesteryl esters to the FAMEs was at least 60% or higher. Phosphatidic acid was the only phospholipid that was not extracted or reacted using the above conditions. This data indicated that most of the lipid compounds are converted to FAMES, thereby increasing the applicability of the automated supercritical method for speciated fat analysis.