The Effect of Frying Conditions on Sunflower Oil Attributes

Abstract

A sample of sunflower oil, produced from Homs Sugar Company, was used in this study to fry local potato by frying under air at household conditions, and frying under pressure (at 150-180ºC, pressure 10-15kg/cm²) for 12 continuous hours without adding new oil. The results were estimated statistically by using Minitab program version 17.0 at level 0.01. The results showed, in both cases of frying, an increase in the physical properties (density, viscosity, refractive index, and coloring degree) of used oil by increasing frying time. A decrease Iodine Number, increase Peroxide Number, increase the percentage of free fatty acids, increase of C16:0 and C18:1 acids percentage, and decrease of C18:2 and C18:3 acids percentage, associated by increasing frying time. But when frying under pressure we noticed that these changes were slow because of the unadequated oxygen presence during frying under pressure. So we can say that the oil was still usable for frying for a long time when frying under pressure more than when frying under air with the vessel is open.