ANALYTICAL METHODS FOR THE ANALYSES OF FOOD LIPIDS BASED ON HIGH RESOLUTION CHROMATOGRAPHY TECHNIQUES

This paper presents various analytical methods, based on high resolution chromatographic techniques, applied to the study of the composition of different food matrices with a predominantly triglyceride composition (butter, oil, lard). Furthermore, the minor lipid component contained in other types of food, such as flour and semolina is also analyzed. In these food lipids wax and steryl esters were analysed. Moreover, a method based on gas-chromatographic analysis is presented for the quantification of cholesterol content in eggs. For the determination of the fatty acid composition in food matrices with predominantly triglyceride composition, two innovative methods of transesterification of triglycerides in pentyl esters and phenethyl esters of fatty acids are presented. Pentyl esters avoid the loss of butyric acid when it is derivatized as methyl ester in GC analysis and phenethyl esters allowed to separate unsaturated fatty acids without degradation if compared to GC analysis.