Abstract

Physicochemical Studies on Sunflower Oil Blended with Cold Pressed Tiger Nut Oil, during Deep Frying Process

Rehab FM Ali and El Anany AM

Blends consisting of sunflower oil and cold pressed tiger nut oil in different proportions were evaluated for various physicochemical parameters over 30 hours of frying process. The phenolic content of native oils was determined. Some physical and chemical parameters (Free Fatty Acid, FFA), Peroxide Value (PV), thiobarbituric acid value, iodine value, Total Polar Compounds (TPC), color and viscosity of fresh and fried blended oils measured at different frying periods. Native and blended oils were heated at 180°C+5°C, then frozen French fries potato were fried every 30 min. Oil samples were taken every 5 hours and the entire continuous frying period was 30 hours. The results showed that phenolic content of cold pressed tiger nut oil was about 3.3 times higher than that of sunflower oil. The analytical data showed that the lowest deterioration during frying process occurred in tiger nut oil and the highest in sunflower. The changes of physicochemical parameters were controlled and significantly (P<0.05) decreased when tiger nut /sunflower oil (W/W) proportions were varied between 20/80 to 50/50. The obtained results indicate that mixing sunflower oil with cold pressed tiger nut oil increased the stability and hence improved the quality of sunflower oil during frying process.