Alternative methods of frying and antioxidant stability in sesame and mustard oils

Shallow and parfrying along with deep frying were carried out in sesame and mustard oils, as alternative modes of frying of potato wedges. A citric acid based antioxidant using BHT was formulated and administered to the oils. The suitability of the frying techniques in oils was assessed by standard physicochemical tests and by DPPH radical scavenging activity for antioxidant efficacy. The safety of the fried product was assessed by estimating the malondialdehyde content. The highest oxidation was observed in deep frying, followed by shallow and parfrying. Parfried sesame oil showed greater decrease in % radical scavenging activity than mustard oil, after fourth frying. A greater increase in malondialdehyde in wedges fried in sesame oil was observed compared to that in mustard oil after fourth frying, indicating a greater stability of the mustard oil on repeated frying. The potency of the formulated antioxidant with respect to control was significant (P<0.05) in oils until the third fry (8 days). Mustard oil was found to be a better choice for frying than sesame oil due to its lower changes in oxidation values and % radical scavenging activity, with repeated frying.