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Title: FATTY AND RESIN ACID ANALYSIS IN TALL OIL PRODUCTS VIA SFE/SFR USING ENZYMATIC CATALYSIS

Author
item Taylor, Scott
item King, Jerry

Submitted to: Journal of Chromatographic Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/2/2001
Publication Date: N/A
Citation: N/A

Interpretive Summary: Tall oil is a byproduct of the process used to make paper, and it is usually fractionated into a number of useful products for the coatings, paper-making, and lubrication industries. Recently, tall oil extracts have also found use as a starting material for the isolation of functional food ingredients which can lower cholesterol in humans. In this study, a sample epreparation method was studied which combines various facets of analysis o tall oil-derived products for their acid composition. The method makes use of a natural catalyst, called an enzyme, to facilitate the formation of analytically-useful derivatives for specific acids in the tall oil matrix. Various enzyme types were evaluated with respect to their propensity to form the required derivatives, and it was found that only specific ones would form the desired derivatives for analysis, under the pressure and temperature, and compressed carbon dioxide conditions used to extract and react the tall oil components. The method is environmentally-benign and protects laboratory analysts from exposure to toxic chemicals and solvents, which are used in the traditional method of analysis of the above tall oil products.

Technical Abstract: Supercritical fluid extraction (SFE) is combined with supercritical fluid reaction (SFR) in an analytical mode to assess tall oil products for their fatty acid and/or resin acid content. The supercritical fluid reaction consists of an in-line enzymatically-catalyzed reaction where a lipase transesterifies specific lipids with methanol. The SFE/SFR sequence is conducted employing commercially-available extractors using supported lipases in the extraction cell to form methyl esters. In this study, six different commercially-available lipases are screened for activity. Extraction/reaction parameters are as follows using supercritical carbon dioxide: 197 bar, 50 deg C, 80 mL extractant fluid at 1 mL/min flowrate, restrictor temperature of 65 deg C, and 1 volume percent modifier (methanol:hexane; 1:1). Extract collection is accomplished in a vial containing hexane (10 mL) cooled to 10 deg C. The SFE/SFR extracts are analyzed by capillary gas chromatography and supercritical fluid chromatography, and compared to tall oil products derivatized by conventional chemical derivatization techniques.