Grasas y Aceites, Vol 58, No 4 (2007)

Assessment of oxidative deterioration of soybean oil at ambient and sunlight storage

Farooq Anwar, Shahzad Ali Shahid Chatha, Abdullah Ijaz Hussain



This study was carried out in order to probe the extent of oxidative alterations in soybean oil (SBO), subjected to ambient and sunlight storage, over a period of 180 days. The magnitude of oxidative changes was monitored by the periodical measurement of peroxide value (PV), color, free fatty acid (FFA) contents, refractive index (RI), p-anisidine-, conjugated dienes-, conjugated trienes-, and iodine- values. At the end of storage period (180 days), the initial contents of FFA (0.02 % as oleic acid) and PV (0.02 meq/kg of oil) of the SBO samples subjected to ambient and sunlight storage reached the level of 1.77, 2.90 % and 20.52, 41.89 meq/kg of oil, respectively. The initial values of RI (40°C) (1.4630), panisidine (1.10), conjugated dienes (0.08) and conjugated trienes (0.04) rose to the point of 1.4647, 1.4659; 36.13, 50.40; 23.97, 41.49 and 13.81, 19.35, respectively. Whereas, the iodine value (g of I /100 g of oil) decreased from 138.00 to 126.18 and 118.04, respectively. At the end of storage period, the overall order, indicative of the oxidative changes in RI, FFA, IV, color (red + yellow), PV, P-anisidine, conjugated dienes and conjugated trienes of the SBO subjected to ambient and sunlight storage was as follows: 1.001:1.002, 1.00:1.65, 0.91:0.86, 0.80:0.60 + 0.75:0.50, 1.00:2.04, 1.00:1.39, 1.00:1.73 and 1.00:1.40, respectively. The results of various parameters investigated in the present study demonstrated the magnitude of oxidative deterioration of the SBO samples exposed to sunlight to be significantly (P < 0.05) pronounced as compared with that of ambient.


Conjugated oxidation products; Oxidation parameters; Peroxide value; Storage; Soybean oil

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American Oil Chemists Society (AOCS). 1997. Official and Recommended Practices of the American Oil Chemists Society, 5th ed., AOCS Press, Champaign IL, USA.

Anwar F, Bhanger MI, Yasmeen S. 2003. Antioxidant activity of some natural extracts in corn oil. in Murata N, Yamada M, Nishida I, Okuyama H, Sekiya J & Hajime W (Eds.) Advanced Research of Plant Lipids, 24-27, Kluwer Publishers, Netherlands.

Cuppett S, Schnepf M, Hall C. 1997. Natural antioxidants – Are they a reality. in Shahidi F (Ed.). Natural Antioxidants, Chemistry, Health Effects and Applications, 12-24, AOCS Press, Champaign IL, USA.

Dobarganes MC, Márquez-Ruiz G. 2003. Oxidized fats in foods. Curr. Opin. Clin. Nutr. Metabolic Care. 6, 157-163. doi:10.1097/00075197-200303000-00004

International Union of Pure and Applied Chemistry (IUPAC). 1987. Standard Methods for the Analysis of Oils, Fats and Derivatives, 7th revised and enlarged ed., edited by C. Paquot and A. Hautfenne, Blackwell Scientific, London.

Khan M, Shahidi F. 2000. Rapid oxidation of commercial extra virgin olive oil stored under fluorescent light. J. Food Lipids. 6, 331-339. doi:10.1111/j.1745-4522.1999.tb00154.x

Khan M, Shahidi F. 2002. Photooxidative stability of stripped and non-stripped borage and evening primrose oil and their emulsions in water. Food Chemistry, 79, 47- 53. doi:10.1016/S0308-8146(02)00176-0

Lawson H. 1995. Food Oils and Fats: Technology, Utilization, and Nutrition, 18-115. Chapman & Hall, New York.

Martín-Polvillo M, Márquez-Ruiz GM, Dobarganes MC. 2004. Oxidative stability of sunflower oils differing in unsaturation degree during long-term storage at room temperature. J. Am. Oil Chem. Soc. 81 (6), 577-583. doi:10.1007/s11746-006-0944-1

McGinely L. 1991. Analysis and quality control for processing and processed fats. in Rossell JB, Printed, JLR, (Eds), Analysis of Oilseeds, Fat and Fatty Food, 440-470, Elsevier Applied Science, New York.

Min DB and Lee HO. 1998. Lipid Oxidation of Edible Oil, Food Lipid: Chemistry, Nutrition and Biochemistry, Akoh CC and and Min DB (Eds.), 283-296, Marcel Dekker, New York.

Naz S, Sheikh H, Saddiqi R, Sayeed SA. 2004. Oxidative stability of olive, corn and soybean oil under different conditions. Food Chemistry, 88, 253-259. doi:10.1016/j.foodchem.2004.01.042

Pan X, Ushio H, Ohshima T. 2004. Photo-oxidation of lipids impregnated on the surface of dried seaweed (Porphyra yezoensis Ueda). Characterization of volatiles. J. Am. Oil Chem. Soc., 81(8), 773-781. doi:10.1007/s11746-004-0977-5

Pezzuto JM, Park EJ. 2002. Autoxidation and antioxidants, in Swarbrick J, Boylan JC, (Eds.), Encyclopedia of Pharmaceuticals Technology, (vol. 1, 2nd ed.) 97-113, Marcel Dekker Inc., New York.

Shahidi F, and Wanasundara UN. 1997. Measurement of lipid oxidation and evaluation of antioxidant activity, in Shahidi F, (Ed.), Natural Antioxidants, Chemistry, Health Effects and Applications, 379-396, AOCS Press Champaign IL, USA.

Sherwin ER. 1978. Oxidation and antioxidants in fats and oils processing. J. Am. Oil. Chem. Soc., 55, 809-814. doi:10.1007/BF02682653

Siddhuraju P, Becker K. 2003. Antioxidant properties of various solvent extracts of total phenolic constituents from three different agroclimatic origins of drumstick tree (M. Oleifera Lam.). J. Agric. Food Chem., 51, 2144-2155. doi:10.1021/jf020444+

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