Determination of cis,cis-Methylene Interrupted Polyunsaturated Fatty Acids in Fats and Oils By Capillary Gas Chromatography

Abstract

A capillary gas chromatographic (CGC) method is described for the determination of cis,cis-methylene interrupted polyunsaturated fatty acids (cis-PUFA) in fats and oils. The sample is saponified and the liberated fatty acids are esterified to the corresponding methyl esters. The latter are analyzed by CGC using a 60M SP2340 capillary column. Area percent values for 9,12-cis,cis-C18:2 and 9,12,15-cis,cis,cis-C18:3 fatty acid methyl esters are summed to give the total cis-PUFA content. Gas chromatographic results agreed well with those obtained by an enzymatic lipoxygenase method at the 31-48% cis-PUFA levels with a correlation coefficient of 0.98. The method has a precision (relative standard deviation) of 0.33% at a 44.4% cis-PUFA level in margarine oil.

Quantification of Generic Salatrim in Foods Containing Salatrim and Other Fats Having Medium- and Long-Chain Fatty Acids

“…The transesterification of coconut oil triacylglycerols into their respective methyl esters was performed using a reagent of boron trifluoride in methanol (BF3/ methanol, 14/100, w/v, purchased from Alltech Associates, Deerfield, IL) with a 0.5 N methanolic sodium hydroxide solution. The transesterification was performed according to the procedure described by Athnasios et al (1986). The gas chromatographic analysis of FAME was performed using a Hewlett-Packard Model 5890 series II gas chromatography equipped with a flame ionization detector (FID).…”