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AOCS Official Method Ce 1h-05
Revised 2017
cis-,trans-, Saturated, Monounsaturated and Polyunsaturated Fatty Acids in Vegetable or Non-Ruminant Animal Oils and Fats by Capillary GLC

DEFINITION
This method provides a gas-liquid chromatography (GLC) procedure for the determination of the fatty acid composition, including the trans fatty acid isomers of vegetable or non-ruminant animal oils and fats. The fatty acid methyl esters (FAME) of the sample are separated on a capillary gas chromatography column having a highly polar stationary phase, according to their chain length (CL), degree of unsaturation, and geometry and position of the double bonds.

This method is specially designed to determine, by a single capillary GLC procedure, the levels of trans isomers, saturated fatty acid (SAFA), cis- and trans-monounsaturated fatty acid (MUFA), and cis- and trans-polyunsaturated fatty acid (PUFA) levels in the same sample and same analysis. For nutritional labeling purposes the total fat, saturated, cis-monounsaturated, cis-polyunsaturated, and trans fatty acid contents may need to be determined.

SCOPE
The method is applicable to crude, refined, partially hydrogenated or fully hydrogenated oils and fats derived from vegetable or non-ruminant animal sources. The method is not suitable for the analysis of dairy, ruminant, marine, long chain polyunsaturated (PUFA) fats and oils, or products supplemented with conjugated linoleic acid (CLA). There is minor co-elution of cis- and trans-fatty acid isomers, particularly in the C18:1 (oleic acid) region, using this technique.