Effect of simultaneous frying of food items on the concentrations and risks of PAHs in edible oils

This study evaluated the effects of simultaneous frying of food items on the concentrations and risks of PAHs in different types of frying oils. The PAH concentrations of these oils were quantified prior to frying and after each frying cycle by using gas chromatography-mass spectrometry (GC–MS). The Ʃ16 PAHs concentrations in the oils before and after frying ranged from 20 to 120 µg kg -1 and 30 to 250 µg kg -1 respectively. There were substantial changes in the individual PAHs and homologue concentrations in these edible oils after four frying cycles. The changes in the PAH concentrations after the frying series were in the sequence of palm olien (POL) > soybean oil (SBO) > groundnut oil (GNO) > coconut oil (CNO) > canola oil (CAO) > sunflower oil. (SFO) > olive oil (OLO) > palm oil (PMO). The observed order is controlled by the interplay between antioxidant compositions, degree of unsaturation and smoke point of the oils. The average changes in the Σ16 PAH concentrations of oil used repetitively for simultaneous frying of different food items were by far higher than the average changes in the PAH concentrations of oil used repetitively for frying of single food item. The concentrations of the high molecular weight PAHs concentrations in the unfried and fried oils were above the limit of 2 µg kg -1 and 5 µg kg -1 for the individual PAH and their sum respectively set by the European Union. The incremental lifetime carcinogenic risk (ILCR) assessment resulting from the ingestion of the unfried and fried edible oils indicates low carcinogenic risk.