EC Pharmacology and Toxicology

Deep fat frying is an important method of food preparation. Chemical reactions occur during frying and give rise to formation of complex products and oxidized fatty acids which are absorbed by the food. The objective of this study was to assess the effect of repeated heating on the peroxidative quality of the frying oils by measuring the Thio Barbituric Acid Reactive Substances “TBARS” content in fresh, heated and repeatedly heated studied oils (sunflower, cottonseed and mixed oils). Results revealed that the deteriorative effect of heat as indicated by the TBARS level in oil, increases by increasing the duration of oil use. The repetition of heating is much more destructive than the continuous use of the oil. Sunflower oil can tolerate heating better than cottonseed and mixed oil. It is recommended that frying is better to be avoided. Repeated use of the oil for frying must not occur even with short periods of use.

Keywords: Frying; Heated Oils; Antioxidants; Tocopherols; Chromatography

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