Supercritical fluid tomato extract for stabilization of perilla oil subjected to thermal treatment

Abstract

There has been increasing concern over the potential carcinogenic problem of the synthetic antioxidants in oil industries. Tomato extract was prepared by supercritical-CO2, which may be a natural antioxidant. The supercritical fluid tomato extract (SFTE) was added in perilla oil (PO) and investigated the oxidative stability of PO and compared with control and those of the PO containing alpha-tocopherol as a positive control. SFTE had a high content of lycopene (64.91%) and beta-carotene (34.93%), which led to significantly higher antioxidant capacity than that of the alpha-tocopherol. During the thermal treatment at 65 degrees C for 24 hr, the PO containing SFTE at various concentrations (100, 300, 500, and 1,000 mu g/ml) showed significantly lower acid value and peroxide value, and at least 1.5 times higher induction period than those of the control and alpha-tocopherol-added PO at the same concentrations. The results suggest that SFTE may be an attractive natural antioxidant in oil industries. Practical Applications Oxidation is a major problem causing the quality deterioration of edible oils which are rich in unsaturated fatty acids. Generally, chemically synthesized antioxidants are widely added to vegetable oils for retarding oxidative deterioration. But, these antioxidants are potentially carcinogenic to human health. SFTE produced in this study can be attractive alternative natural antioxidant over widely used alpha-tocopherol and chemically synthesized antioxidants for preventing the lipid oxidation in food industries.