The effect of superheated steam treatment on the quality of vegetable oils

Abstract

The changes in the quality of three vegetable oils: soybean oil, corn oil and cotton seed oil, occurring during heating in superheated steam (SHS) were compared with the changes occurring during heating in hot air (HA). The temperature of both the SHS and the HA was 180°C, and the heating time ranged from 30 to 180 minutes. The quality of the oils was investigated by evaluating the acid value, peroxide value, viscosity, color and odor. The acid value, the peroxide value and the viscosity of the oils heated in SHS were lower than those of the oils heated in HA. SHS-treated oils retained their fresh oil color and odor, whereas HA-treated oils changed their color and odor remarkably. Therefore, the influence of the SHS treatment on the oil quality was not significant.