Grasas y Aceites, Vol 70, No 1 (2019)

Effects of heating temperature on the tocopherol contents of chemically and physically refined rice bran oil

M. H. Bruscatto
Department of Science and Food Technology, Federal University of Pelotas, Brazil

V. R. Pestana-Bauer
Institute Federal Rio Grandense , Campus Visconde da Graça, Brazil

D. M. Otero
Department of Science and Food Technology, Federal University of Pelotas, Brazil

R. C. Zambiazi
Department of Food Science, Federal University of Pelotas, Brazil


The stability of α-, (β+γ)- and δ-tocopherols present in rice bran oil at different heating temperatures has been evaluated. For this purpose, samples of rice bran oil from chemical and physical refining processes in Brazilian industries were studied. The oils were submitted to cabinet drying without air circulation in the absence of light at 100 ºC, 140 ºC and 180 ºC. The samples were taken before heating and after 48, 144, 240, 336, 432, 576, 768, 1008 and 1368h of heating. The analyses of tocopherols were made by high performance liquid chromatography, with a fluorescence detector. It was determined that α-tocopherol was the compound with the fastest degradation rate at the three heating temperatures. The highest degradation rate of tocopherols in both oils occurred at 180 ºC. Among the tocopherols studied, α tocopherol presented the lowest stability, followed by (β+γ)- and δ-tocopherols.


Antioxidant; Chemical refining; Physical refining; Temperature

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Alpaslan MS, Tepe S, Fiimsek O. 2001. Effect of refining processes on the total and individual tocopherol content in sunflower oil. Int. J. Food Sci. and Tech. 36, 737–739.

Azlan A, Ismail M, Abdul Hamid A. 2008. Extraction and determination of oryzanol in rice bran of mixed herbarium UKMB; AZ 6807: MR 185, AZ 6808: MR 211, AZ6809: MR 29. ASEAN F. J. 15, 89–96.

Chu YH, Lin JY. 1993. Factors affecting the content of tocopherol in soybean oil. J. Am. Oil Chem. Soc. 70, 1263–1268.

Cunha SC, Amaral JS, Fernandes JO, Oliveira MBPP. 2006. Quantification of tocopherols and tocotrienols in Portuguese olive oils using HPLC with three different detection systems. J. Agric. Food Chem. 54, 3351–3356. PMid:16637695

Ferrari RA, Schulte E, Esteves WL, BrühlK D, Mukherjee J. 1996. Minor constituents of vegetable oils during industrial processing. Amer. Oil Chem. Soc. 73, 587–592.

Flohé RB. 2006. Bioactivity of vitamin E. Nutr. Res. Rev. 19, 174–186. PMid:19079884

Kalucka MN, Korczak J, Elmadfa I, Wagner KH. 2005. Effect of ?- and ?-tocopherol on the oxidative stability of a mixed hydrogenated fat under frying conditions. Eur. Food Res. Technol. 221, 291–297.

Ko SN, Kim CJ, Kim CT, Kim H, Chung SH, Lee SM, Yoon HH, Kim IH. 2003. Changes of vitamin E content in rice bran with different heat treatment. Eur. J. Lipid Sci. Technol. 105, 225–228.

Lampi AM, Kamal-Eldin A. 1998. Effect of ?- and ?-tocopherols on thermal polymerization of purified high-oleic sunflower triacylglycerols. J. Am. Oil Chem. Soc. 75, 1699–1703.

Martins PF. 2006. Estudos e experimentos para a concentração de tocoferóis e fitosteróis por meio da destilação molecular. Tese (Doutorado em Engenharia Química), Universidade estadual de Campinas, Faculdade de Engenharia Química, Campinas, Brasil, pp. 224.

Morrissey PA, Sheehy JA. 1999. Optimal nutrition: vitamin E. Proc. Nutr. Soc. 58, 459–468. PMid:10466191

Nissiotis M, Tasioula-Margari M. 2002. Changes in antioxidant concentration of virgin olive oil during thermal oxidation. Food Chem. 77, 371–376.

Nolasco SM, Aguirrezábal LAN, Crapistec GH. 2004. Tocopherol oil concentration in field-grown sunflower is accounted for by oil weight per seed. J. Am. Oil Chem. Soc. 81, 1045–1051.

Pestana VR, Zambiazi RC, Mendonça CR. 2008a. Farelo de arroz: características, benefícios à saúde e aplicações. Boletim Ceppa 26, 29–40.

Pestana VR, Zambiazi RC, Mendonça CR, Bruscatto MH, Lerma-Garcia MJ, Ramis-Ramos G. 2008b. Quality Changes and Tocopherols and ?-Orizanol Concentrations. J. Am. Oil Chem. Soc. 85, 1013–1019.

Pestana VR, Zambiazi RC, Mendonça CR, Bruscatto MH, Ramis-Ramos G. 2009. Influencia del procesado industrial sobre las características químico-físicas y contenido en lípidos y antioxidantes del salvado de arroz. Grasas Aceites 60, 184–193.

Player ME, Kim HJ, Lee HO, Min DB. 2006. Stability of ?-, ?- or ?- tocopherol during soybean oil oxidation. J. Food Sci. 71, 456–460.

Rennick KA, Warner K. 2006. Effect of elevated temperature on development of tocopherol quinones in oils. J. Agric. Food Chem. 54, 2188–2192. PMid:16536594

Romero N, Robert P, Masson L, Ortiz J, González K, Tapia K, Dobarganes C. 2007. Effect of ?-tocopherol, ?-tocotrienol and rosa mosqueta shell extract on the performance of antioxidant-stripped canola oil (Brassica sp.) at high temperature. Food Chem. 104, 383–389.

Rosli WIW, Babji AS, Aminah A, Foo SP, Malik ABD. 2006. Vitamin e contents of processed meats blended with palm oils. J. Food Lipids 13, 186–198.

Salem EG, El Hissewy A, Agamy NF, El Barry DA. 2014. Assessment of the quality of bran and bran oil produced from some Egyptian rice varieties. The Journal of the Egyptian Public Health Association 89, 29–34. PMid:24717398

Statsoft 2004. Inc. Statistica for windows. Versão 7.0. Tulsa, OK.

Steel CJ, Dobarganes MC, Barrera-Arellano D. 2005. The influence of natural tocopherols during thermal oxidation of refined and partially hydrogenated soybean oils. Grasas Aceites 56, 46–52.

Tasan M, Demirci M. 2005. Total and individual tocopherol contents of sunflower oil at different steps of refining. Eur. Food Res. Technol. 220, 251–254.

Zambiazi R. 1997. The role of endogenous lipid components on vegetable oil stability. Tesis (Doctorado), Food and Nutritional Sciences Interdepartmental Program, University of Manitoba. Manitoba, Canadá, pp.304.

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