مهدی محمدی

Purpose – The purpose of this paper is to determine the peroxide value (PV), p-anisidine and total oxidation value (TOTOX) values of imported edible oils in Iran. Design/methodology/approach – A total 196 oil samples of different origin and types (corn, olive, canola and grape-seed oil) were collected randomly from Boushehr port of Iran and a total 27 oil samples were also collected from frying pans used to deep-fry local food items at different restaurants in Boushehr city. Findings – The PVs ranged from 1.38-13.74, 3.90-20.00, 0.83-2.99, 0.67-11.95 and 0.00-9.96 mequiv/kg found in refined olive oil, virgin olive oil, canola oil, grape-seed oil and corn oil, respectively. The results showed that PVs of 18.37 percent of imported oil and 62.96 percent of frying oils from restaurant exceeded the maximum acceptable limits set by Institute of Standards and Industrial Research of Iran (ISIRI) (2-20 mequiv/kg for different types of oils). P-anisidine value ranged from 0.89-27.56 mequiv/kg in imported oils and 2.21-30.76 mequiv/kg found in frying oil from restaurants. The TOTOX value increased linearly with peroxide values and p-anisidine values. It ranged from 0.89-76.62. Originality/value – Fried foods are very common in Iranians’ diet. A major portion of the edible oils in Iran are imported from other countries through Boushehr port. ISIRI has set maximum acceptable limit for PVs in different oils imported to the country. The possible effects of storage on oil oxidation are the original criteria of this research. The results of the study indicate that inappropriate storage of edible oils and their use in frying applications at restaurants facilitate oil oxidation and deterioration.