Tocopherols in vegetable oils

Determination of tocopherols in vegetable oils Determination of tocopherols and tocotrienols in rice bran Determination of tocopherols in tomato... 

Chase, G.W. Jr., Akoh, C.C., and Eitenimiller, R.R. 1994. Analysis of tocopherols in vegetable oils by high-pressure liquid chromatography Comparison of fluorescence and evaporative lightscattering detection. J. Am. Oil. Chem. Soc. 71 877-880. 

Lerma-Garcia, M.J. Simo-Alfonso, E.F. Ramis-Ramos, G. Flerrero-Martinez, J.M. 2007. Determination of tocopherols in vegetable oils by CEC using methylacrylate ester-based monolithic columns. Electrophoresis. 28 4128 135. 

Silva, S.D. Rosa, N.F. Ferreira, A.E. Boas, L.V. Bronze, M.R. 2009. Rapid determination of a-tocopherol in vegetable oils by fourier transform infrared spectroscopy. Food Anal. Methods. 2 120-127. 

Table 9.5. Tocopherols in vegetable oils, fish and animal fats (ppm or mg/kg) ...

Figure 11 Separation of tocopherols in vegetable oils by SFC. Chromatographic conditions Column, L-column, ODS, 5 im, 250 X 4.6 mm mobile phase, COj methanol, (99.5 0.5, w/w) detection, UV, 290 nm. Peak identification 1, tocol (internal standard) 2, 5-tocopherol 3, 3-tocopherol 4, y-tocopherol 5, a-tocopherol. (From Ref. 144.)...

Andres, M. P. S., J. Otero, and S. Vera. 2011. High performance liquid chromatography method for the simultaneous determination of a-, P-, and y-tocopherol in vegetable oils in presence of hexadecyltrimethylammonium bromide/w-propanol in mobile phase. Food Chem. 126 1470-1474. 

Diaz, T. G., I. D. Meras, M. I. Rodriguez Caceres, and B. R. Murillo. 2006. Comparison of fluorimetric signal for simultaneous multivariate determination of tocopherols in vegetable oils. Appl. Spectrosc. 60 194-202. 

Non-aqueous capillary electrophoresis with fluorimetric detection was also successfully used for the determination of tocopherols in vegetable oils (Galeano-Diaz et al., 2012). Infrared (IR) spectroscopy was also employed for tocols quantification (Ahmed et al., 2005 Zahir et al., 2014). In order to complete this overview, various methods for quantitative analysis of tocopherols were compared (Koswig Morsel, 1990). 

Galeano-Diaz, T., Acedo-Valenzuela, M. I. Silva-Rodriguez, A. (2012). Determination of tocopherols in vegetable oil samples by non-aqueous capillary electrophoresis (NACE) with fluorimetric detection. J. Food Comp. Anal, 25, 24-30. 

C Mariani, G Bellan. Content of tocopherols, deidrotocopherols, tocodienols, tocotrienols in vegetable oils. Riv Ital Sostanze Grasse 73 533-543, 1996. (In Italian.)... 

This approach can be extended to a large number of natural products rich in compounds with desirable biological activity, which include fruits and other plants -for example, the recovery of phytosterols and tocopherol from vegetable oils, as well as natural marine products. 

Tocopherols can be analysed readily in vegetable oils by normal phase HPLC with UV or fluorescence detection. A standard method is described by AOCS (1998). 

Vitamin E, (tocopherols) C29H50O2 (Figure 6.8), which acts as an anti-oxidant to prevent the free radical oxidation of lipids in cell membranes. There are sufficient supplies of vitamin E in vegetable oils. 

Puspitasari-Nienaber, N.L. Ferruzzi, M.G. Schwartz, S.J. 2002. Simultaneous detection of tocopherols, carotenoids, and chlorophylls in vegetable oils by direct injection C30 RP-HPLC with coulometric electrochemical array detection. J. Am. Oil Chem. Soc. 79 633 640. 

Ahmed, M.K. Daun, J.K. Przybylski, R. 2005. FT-IR based methodology for quantitation of total tocopherols, tocotrienols, and plastochromanol-8 in vegetable oils. J. Food Comp. Anal. 18 359-364. 

Commercially, tocopherol is available as a pure all-rac-a-tocopherol, mixed tocopherols having various contents of a-, p-, y-, or 8-tocopherols (diluted in vegetable oil) and synergistic mixtures containing tocopherols, ascorbyl palmitate or other antioxidants, and synergists such as lecithin, citric acid, and carriers. Extraction of tocopherols from natural sources and chemical synthesis of tocopherols are well described by Schuler (100). 

Deodorization There are no major differences between deodorization procedures for sunflower oil and other vegetable oils. The loss of tocopherols in the oil is worth noting for sunflower oil, though. The average tocopherol content of sunflower oil is medium (440-1520 ppm, according to Codex-Stan 210-1999), nearly all of which is alpha-tocopherol (403-935 ppm). Table 18 shows the reduction in the tocopherol content upon deodorization of sunflower oil (69). Tocopherols may be recovered from the distillate of deodorization. 

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