Analysis of triglycerides

Supercritical fluid chromatography has found many applications in the analysis of polymers, fossil fuels, waxes, drugs, and food products. Its application in the analysis of triglycerides is shown in Figure 12.38. 

Example of the application of supercritical fluid chromatography to the analysis of triglycerides. (Chromatogram courtesy of Alltech Associates, Inc. Deerfield, IL). 

HPLC has many applications in the food industry. Two of interest in the bakery sector are the analysis of triglycerides and wheat proteins. 

C. Litchfield, Analysis of Triglycerides, Academic Press, New York (1972). 

Until now, electrokinetic mode of sample injection was employed in the majority of CEC analyses. Ross et al. [16] compared the reproducibility of both electrokinetic (20 kV/5 s) and hydrodynamic injection (5 bar/15 s). The relative standard deviation (r.s.d.) for retention times (n=5) varied between 0.26-0.37% and 0.28-0.40% for electrokinetic and hydrodynamic injection, respectively. The r.s.d. (n=5) for the peak heights varied between 0.81-1.64% and 2.81-3.80% for electrokinetic and hydrodynamic injection, respectively. Sandra et al. confirmed this accuracy for the analysis of triglycerides [18],... 

Byrdwell, W.C. and Emken, E.A. (1995) Analysis of triglycerides using atmospheric-pressure chemical ionization mass-spectrometry. Lipids, 30(2), 173-175. 

Lipp, M., Simoneau, C. and Anklam, E. (1996) Analysis of triglycerides from cocoa butter, vegetable... 

Simoneau, C., Hannaert, P. and Anklam, A. (1999) Detection and quantification of cocoa butter equivalents in chocolate model systems analysis of triglyceride profiles by high resolution GC. Food Chem., 65, 111-116. 

Amate, L., Ramirez, M. and Gil, A. (1999) Positional analysis of triglycerides and phospholipids rich in long chain polyunsaturated fatty acids. Lipids, 34, 865-871. 

Collomb, M., Buetikofer, U., Spahni, M. and Buehler, T. (1998a) Analysis of triglycerides. Comparison of methods of MLR, PLS and PCA regression for the determination of foreign fats in milk fat using capillary GC. Mitt. Gebiete Lebensm. Hyg., 89, 617-624. 

Lercker, G., Frega, N., Bocci, F. and Bertacco, G. (1992) Milk fat. Gas chromatographic analysis of triglycerides in assessment of authenticity of butter. Scienza Tecnica Lattiero Casearia, 43, 95-110. 

Lipp, M. (1995) Review of methods for the analysis of triglycerides in milk fat application for studies of milk quality and adulteration. Food Chem., 54, 213-221. 

Analysis of triglycerides of oils and fats. Rev. Franc. Corps Gras, 33, 437—445. 

Schneller, R. and Wullschleger, R. (1992) Quantitative determination of milk fat in fat mixtures by gas chromatographic analysis of triglycerides. Mitt. Gebiete Lebensm. Hyg., 83, 737-744. 

European Commission. 1999. Reference method for the detection of foreign fats in milk fat by gas chromatographic analysis of triglycerides - revision 1. Commission Regulation (EC) No 2771/1999 Annex II. Official Journal of the European Communities L 333/23. 

Figure 11. Stereospecific analysis of triglycerides by the Brockerhoff method (132). The numbers 1, 2, and 3 on the glycerol symbol refer to the fatty acids at the sn-I-, sn-2-, and sn-3-positions, respectively, of the original triglyceride phenylphosphate group.

W.C. Byrdwell, E.A. Emken, Analysis of triglycerides using APCI-MS, Lipids, 30 (1995) 173. 

Not only the analysis of triglycerides can be done using GC/MS. The EI+ mass spectra of other lipids with relatively small molecules are known. As an example, Figure 8.1.2 shows the mass spectrum for dipalmitoylphosphatidylethanolamine in EI+ standard conditions. 

Figure 7.3. HPLC analysis of triglycerides in olive oil using nonaqueous reversed-phase chromatography with refractive index detection. Reprinted with permission from reference 11.

Litchfield, C. (ed.) (1972) Distribution of fatty acids in natural triglyceride mixtures, in Analysis of Triglycerides, Academic Press, New York, NY, pp. 233-264. 

Figure 9. Analysis of triglycerides in whole butter on a 20 m X 0.30 mm SE-52 column with a stationary phase film thickness of 0.05 pm and the on-column injection technique. (12)...

The direct analysis of triglycerides by GLC is currently a reasonably standard procedure, although differences in response factors for carbon numbers are very common (Karleskind et al., 1974 Hamilton and Ackman, 1975 Kuksis eta/., 1975 Myher, 1978 Aneja et al., 1979 Grob, 1979, 1981 Monseigny et al., 1979 Grob et al., 1980 D Alonzo et al., 1981). 

Phillips, BE Smith, CR. Stereospecific analysis of triglycerides from Mannina emarginata seed oil. Lipids, 1972, 7, 215-217. 

The separation of triglycerides using partition chromatography can be done both in RP and normal-phase columns. RP columns have given better results with nonaqueous mobile phases (for instance, acetonitrile acetone), which allow separation of triglycerides according to the equivalent carbon number. Normal-phase silica columns have been used for analysis of triglycerides, which is a classical application of this type of column. The main... 

A detailed investigation of the operating conditions of the TLC-FID system for the analysis of triglycerides, and for important ingredients in the food-processing and confection industry (e.g. monoglycerides and diglycerides) has been recently carried out by Peyrou et al (1996). 

Byrdwell, W. C., Emken, E. A., Neff, W. E. and Adlof, R. O. (1996) Quantitative analysis of triglycerides using atmospheric pressure chemical ionisation mass spectrometry. LipidSy 31,919-35. 

Schuyl, P. J. W., de Joode, T., Duchateau, G. S. M. J. E. and Vaconcellos, M. A. (1995) HPLC-MS analysis of triglycerides, in Proceedings of the 43rd/ASMS Conference on Mass Spectrometry and Allied Topics, Atlanta, GA, 21-26 May, American Society for Mass Spectrometry, p. 1143. 

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