Evaluation the separated and combined effect of Mentha aquatic extract in stabilizing of sunflower oil under thermal condition

The extracts of Mentha aquatique by ultrasound assisted and maceration (ethanol: water (80:20)) extraction method were compared. The total phenolic content of extracts were obtained 45.16 mg GA/g and 51.92 mg GA/g Extract in maceration and ultrasound-assisted method respectively. The antioxidant activity of different concentration of extracts (50, 100, 250, 500, 1000 and 1500 ppm) were measured by DPPH radical scavenging method. The results shows that in both extracts by increasing in concentration of extract antioxidant activity were increased. Both extract at 1000 ppm of concentration have no significant statistical difference by TBHQ and they selected to add in sunflower oil. The thermal stability of samples containing separated and mixture extracts (1000 ppm) evaluated at 180 °C. TBHQ at 100 ppm served as standard besides the control. The results showed that during frying process oil oxidation were increased. Control sample had the least oxidative stability and sample containing mix extract showed the highest oxidative stability. Finally 1000 ppm of the mix extract could act better than 100 ppm TBHQ in inhibition of lipid oxidation in sunflower oil during frying process and it suggest as a natural antioxidant to use in edible oils