A Physiological Impact: Understanding the Health Risks of Thermo-Oxidized Rice Bran Oil

Abstract

Thermal processing alters the chemical composition and health implications of vegetable oils, which are essential to the diet. This study investigates the compositional alterations and physicochemical characteristics of rice bran oil after 4 and 8 hours of thermal treatment at 180°C, utilizing gas chromatography. The observed values for normal and thermo-oxidized oil ranged as follows: acid value (0.36–2.39), specific gravity (0.9013–0.8893), refractive index (1.461–1.512), p-anisidine value (4.95–19.49), saponification value (182–194), peroxide value (0.56–8.5), and iodine value (104–89). Gas chromatography showed trans fats and substantial monounsaturated and polyunsaturated fatty acid alterations. In Wistar rats, a preclinical study showed alterations in oxidative stress indicators such as glutathione, catalase, SOD, and TBARS, as well as lipid profiles and hepatic enzyme levels. These results suggest that consumption of thermo-oxidized rice bran oil may have deleterious physiological effects, highlighting the importance of dietary oil quality in public health.