Effect of Refining and Thermal Processes on Olive Oil Properties

Authors
M. S. Mirrezaie Roodaki 1
M. A. Sahari 2
B. Ghiassi Tarzi 1
M. Barzegar 2
M. Gharachorloo 1
1 Department of Food Science and Technology, Science and Research Branch, Islamic Azad University, Tehran, Islamic Republic of Iran.
2 Department of Food Science and Technology, Faculty of Agriculture Tarbiat Modares University, Tehran, Islamic Republic of Iran.
Abstract
Olive cultivars Bladi and Arbequina were collected and their oil was extracted (cold press). Oil was refined under bleaching and deodorization conditions for 30 minutes at 55-50°C and their property was compared with the virgin olive oil. Virgin and refined oils of the cultivars were processed by fryer heating at 180°C (intervals of 0, 1, 2, 4, and 8 hours) and indexes of fatty acid, free fatty acid, peroxide, thiobarbituric acid, polar compounds, conjugated dienes and trienes, Rancimat, color, total polyphenol, tocopherol, chlorophyll and carotenoid were compared. Results showed that these oils mainly contained oleic (48.69-60.18%), palmitic (18.31-27.02%), linoleic (7.54-18.58%), palmitoleic (3.9-3.08%), stearic (1.78-2.53%), and linoleic acids (1.87-0.22%). According to the results, it was recommended to refine virgin olive oil by mild bleaching and deodorization to save bioactive compounds. Due to the heating condition, the relative amounts of unsaturated fatty acids (22.37-50.6%), polyphenols, tocopherols, chlorophyll, carotenoid and oxidative stability decreased and the relative amounts of saturated fatty acids (14.2-17.1%), acidity, peroxide, conjugated dienes and trienes, polar compounds, and thiobarbituric acid increased significantly, but the colorant initially decreased and then increased (P< 0.05). Due to polar compounds, for frying process, mild refined oil was better than extra virgin oil.

Keywords

1. Adam, S. Kh., Aziz Sulaiman, N., Mat Top, A. G. and Jaarin, K. 2007. Heating Reduces Vitamine Content in Palm and Soy Oils. Malays. J. Bio-chem. Mol Biol., 15: 76-79.
2. Aliakbarian, B., De Faveri, D., Casazza, A. A., Oliveira, R. P. S., Oliveira, M. N., Converti, A. and Perego, P. 2011. Bio-extraction of Olive Oil: Improvement of Quality and Extraction Outputs. Available at: http://www.aidic.it/IBIC2008/webpapers/103Aliakbarian.pdf
3. Allouche, Y., Jiménez, A., Gaforio, J. J., Uceda, M. and Beltrán, G. 2007. How Heating Affects Extra Virgin Olive Oil Quality Indexes and Chemical Composition. J. Agric. Food. Chem., 55: 9646–9654.
4. Andrikopoulos, N. K., Dedoussis, G. V. Z., Falirea, A., Kalogeropoulos, N. and Hatzinikola, H. S. 2002. Deterioration of Natural Antioxidant Species of Vegetable Edible Oils during the Domestic Deep-frying and Pan-frying of Potatoes. Int. J. Food. Sci. Nutr., 53: 351-363.
5. AOCS. 2004. Official Methods and Recommended Practices of the American Oil Chemists’ Society. 5th Edition, AOCS Press, Champaign.
6. Bastida, S. and Sanchez-Muniz, F. J. 2001. Thermal Oxidation of Olive Oil, Sunflower Oil and a Mix of Both Oils during Forty Discontinuous Domestic Frying of Different Food. Food. Sci. Technol. Int., 7: 15-21.
7. Bester, E., Butinar, B., Bucar-Miklavcic, M. and Golob, T. 2008. Chemical Changes in Extra Virgin Olive Oils from Slovenian Istra after Thermal Treatment. Food. Chem., 108: 446–454.
8. Boskou, D. 2006. Olive Oil: Chemistry and Technology. American Oil Chemists’ Society Press, 331 PP.
9. BS. 1976. Fats and Fatty Oils: Determination of Carotene in Vegetable Oils. British Standards. 1976. Methods of Analysis of Fats and Fatty Oils. Other Methods. Determination of carotene in vegetable oil. BS No. 684-2.20: 1977. BSI. shop.bsigroup.com
10. Carrasco-Pancorbo, A., Cerretani, L., Bendini, A., Segura-Carretero, A., Del Carlo, M., Gallina-Toschi, T., Lercker, G., Compagnone, D. and Fernaä Ndez-Gutieä Rrez, A. 2005. Evaluation of the Antioxidant Capacity of Individual Phenolic Compounds in Virgin Olive Oil. J. Agric. Food. Chem., 53: 8918-8925.
11. Casal, S., Malheiro, R., Sendas, A., Oliveira, B. P. P. and Pereira, J. A. 2010. Olive Oil Stability under Deep-Frying Conditions. Food. Chem. Toxicol., 48: 2972–2979.
12. Che Man, Y. B. and Jaswir, I. 2000. Effect of Rosemary and Sage Extracts on Frying Performance of Refined, Bleached and Deodorized (RBD) Palm Olein during Deep-fat Frying. Food Chem., 69: 301-307.
13. Che Man, Y. B. and Tan, C. P. 1999. Effects of Natural and Synthetic Antioxidants on Changes in Refined, Bleached, and Deodorized Palm Olein during Deep-fat Frying of Potato Chips. J. Am. Oil Chem. Soc., 76: 331-339.
14. Farhoosh, R., Haddad Khodaparast, M. H., Sharif, A. and Alavi Rafiee, S. 2013. Effect of Initial Quality and Compositional Parameters on Total Polar Compounds Formation during Continuous Heating of Olive Oil. J. Agr. Sci. Tech., 15: 527-535.
15. Firestone, D. 2005. Bailey’s Industrial Oil and Fat Products. (Ed.): Shahidi F.. A John Wiley and Sons Inc. Atlantic Canada, Memorial University of Newfoundland, 2: 306-327.
16. Ghavami, M., Gharachorloo, M. and Ezatpanah, H. 2003. Effect of Frying on the Oil Quality Properties Used in the Industry Potato Chips. J. Agric. Sci., 9: 1-15. (in Farsi).
17. Ghodsvali, A., Haddad Khodaparast, M. H. and Diosady, L. L. 2008. Aqueous Extraction of Virgin Olive Oil Using Industrial Enzymes. 18th National Congress on Food Technology, Mashhad, Iran.PP. 1-6.
18. Harwood, J. L. and Aparicio, R. 2000. Handbook of Olive Oil: Analysis and Properties. Springer Publishing, 620 PP.
19. Hashempour, A., Fotohi Ghazvini, R., Bakhshi, D. and Asadi Sanam, S. 2010. Effect of Kazeroon’s Climate on Qualitative Indexes of Olive Oil (Olea europeae L.) in Some Cultivars such as Zard, Roghani and Mary. Iran. J. Horticul. Sci., 41: 47-53. (in Farsi).
20. IOC. 2009. International Olive Council Standards for Olive Oil. COI/T.20/Doc. www.internationaloliveoil.org.
21. ISO. 2000. Animal and Vegetable Fats and Oils: Determination of Refractive Index. International Organization for Standardization Standards No. 6320. www.iso.org
22. Jaswir, I. and Che Man, Y. B. 1999. Use Optimization of Natural Antioxidants in Refined, Bleached, and Deodorized Palm Olein during Repeated Deep-fat Frying Using Response Surface Methodology. J. Am. Oil Chem. Soc., 76: 341–348.
23. Jaswir, I., Che Man, Y. B. and Kitts, D. D. 2000. Synergistic effects of Rosemary, Sage, and Citric acid on Fatty Acid Retention of Palm Olein during Deep-fat Frying. J. Am. Oil Chem. Soc., 77: 527-533.
24. Katragadda, H. R., Fullana, A., Sidhu, S. and Carbonell-Barrachina, A. A. 2010. Emissions of Volatile Aldehydes from Heated Cooking Oils. Food Chem., 120: 59–65.
25. Najafian, L., Ghodsvali, A., Haddad Khodaparast, M. H. and Diosady, L. L. 2009. Aqueous Extraction of Virgin Olive Oil Using Industrial Enzymes. Food. Res. Int., 42: 171–175.
26. Noorali, M., Barzegar, M. and Sahari, M. A. 2014. Sterol and Fatty Acid Compositions of Olive Oil as an Indicator of Cultivar and Growing Area. J. Am. Oil Chem. Soc., 91: 1571-1581.
27. Orozco, M. I., Priego-Capote, F. and Luque De Castro, M. D. 2011. Influence of Deep Frying on the Unsaponifiable Fraction of Vegetable Edible Oils Enriched with Natural Antioxidant. J. Agric. Food. Chem., 59: 7194–7202.
28. Quilesa, J. L., Ramırez-Tortosaa, M. C., Gomezd, J. A., Huertasa, J. R. and Mataixa, J. 2002. Role of Vitamin E and Phenolic Compounds in the Antioxidant Capacity, Measured by ESR, of Virgin Olive, Olive and Sunflower Oils after Frying. Food Chem., 76: 461–468.
29. Ramırez, M. R., Morcuende, D., Estevez, M. and Cava, R. 2004. Effects of the Type of Frying with Culinary Fat and Refrigerated Storage on Lipid Oxidation and Colour of Fried Pork Loin Chops. Food. Chem., 88: 85–94.
30. Reboredo-Rodríguez, P., González-Barreiro, C., Cancho-Grande, B., Fregapane, G., Salvador, M. D. and Simal-Gándara, J. 2015. Characterisation of Extra Virgin Olive Oils from Galician Autochthonous Varieties and Their Co-Crushings with Arbequina and Picual cv. Food Chem., 176: 493–503.
31. Salvador, M. D., Aranda, F. and Fregapana, G. 2001. Influence of Fruit Ripening on Cornicabra Virgin Olive Oil Quality: A Study of Four Successive Crop Season. Food Chem., 73: 43-53
32. Silva, S. F., Anjos, C. A. R., Cavalcanti, R. N., Celeghini, R. M. d. S. 2015. Evaluation of Extra Virgin Olive Oil Stability by Artificial Neural Network. Food Chem., 179: 35–43.
33. Takeoka, G. R., Full, G. H. and Dao L. T. 1997. Effect of Heating on the Characteristics and Chemical Composition of Selected Frying Oils and Fats. J. Agric. Food. Chem., 45: 3244-3249.
34. Tena, N., Diego, L., Gonzalez, G. and Aparicio, R. 2009. Evaluation of Virgin Olive Oil Thermal Deterioration by Fluorescence Spectroscopy. J. Agric. Food. Chem., 57: 10505–10511.
35. Velasco, J. and Dobarganes, C. 2002. Oxidative Stability of Virgin Olive Oil. Eur. J. Lipid. Sci. Technol., 104: 661–676.
36. Xu, X. Q., Tran, V. H., Palmer, M., White, K. and Salisbury, Ph. 1999. Chemical and Physical Analyses and Sensory Evaluation of Six Deep-frying Oils. J. Am. Oil Chem. Soc., 76: 1091-1099.
37. Yaghmur, A., Aserin, A., Mizrahi, Y., Nerd, A. and Garti, N. 2001. Evaluation of Argan Oil for Deep-fat Frying. Lebensm. Wiss. u. Technol., 34: 124- 130.
Journal of Agricultural Science and Technology
Volume 18, Issue 3
May and June 2016
Pages 629-641