Daniele Naviglioa, Alessandro Salvatia, Armando Zarrellia, Federica Improdaa, Monica Gallob

aDipartimento di Scienze Chimiche, Università degli Studi di Napoli Federico II, 80126 Napoli, Italy,
bDipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, 80131 Napoli, Italy.

In the food sector, for quality control, fraud detection and authentication of butter fat and other oils and fats, three methods have been developed, one for triglyceride analysis and two for fatty acids analysis. The various analytical methods, based on high resolution chromatographic techniques, have been applied to the study of the composition of different food matrices with one composition mainly of triglycerides (butter, olive oil, lard) [1]. In addition, it is also analyzed the minor lipid component contained in other types of food, such as flour and semolina. In these foods were analyzed for wax and sterol esters. For the determination of the composition of fatty acids in food matrices with composition mainly of triglycerides, two innovative methods of transesterification of triglycerides in the pentyl and phenethyl esters of fatty acids. Conversion to pentyl esters of fatty acids avoids the loss of butyric acid compared to when sampling fatty acids they are derivatized as methyl esters of fatty acids. Finally, in the HPLC analysis the conversion of fatty acids in the phenethyl esters allowed to separate the unsaturated fatty acids without degradation compared to GC analysis. Also, using the same capillary column (RTX 65-TG) with 65% phenyl-35% methyl silicon stationary phase, a method is presented based on gas chromatographic analyzes for the quantification of cholesterol content in eggs [2] and the determination of cholesterol content in egg-pasta to establish total number of eggs added to semolina [3]. Wax esters and steryl esters were determined in olive oil; this procedure was proposed as an alternative method to the procedure proposed by EEC Regulation 183/93 and by using RTX 65-TG capillary column separation of analytes was improved in respect of capillary column 5% phenyl methylsilicone [4].

Keywords: fatty acids, triglycerides, GC, HPLC

References

1. Naviglio D., Dellagreca M., et al., Journal of Food Quality, 1 (2017) DOI: 10.1155/2017/9698107 

2. Naviglio D., Gallo M., et al., Food Chemistry, 132 (2012), 701-708, DOI:  10.1016/j.foodchem.2011.11.002

3. Naviglio D., Langella C., et al., Foods,131 (2018), DOI: 10.3390/foods7090131 

4. Nota G., Naviglio D., et al., J. Agric. Food Chem, 47 (1999), 202-205. DOI: 10.1021/jf980648j