18B-23 |
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J. LEE, K. Kim, and E. Choe. Dept. of Food & Nutrition, Inha Univ., 253 Younghyundong Namgu, Incheon, 402-751, South Korea Sesamol has been reported as an antioxidant in the oil oxidation. Effects of other lignan compounds, sesamin or sesamol, in roasted sesame oil on the oil oxidation during heating are not clearly found. This study investigated the antioxidant activity of sesamol, sesamin, and sesamolin on the oxidation of sunflower oil during heating. Tocopherol-stripped sunflower oil (TSSO) with or without lignan compounds (sesamol, sesamin, and sesamolin) was heated at 180oC for 10 h. Concentrations of each lignan compound in TSSO were 500, 1,000, and 2,000 ppm. Oxidation of oil during heating was evaluated by determining conjugated dienoic acid (CDA) contents, p-anisidine values (PAV), and fatty acid compositions. Concentrations of lignan compounds in the oil during heating were also monitored by high performance liquid chromatography. CDA contents and PAV of TSSO increased with heating time due to the oxidation of TSSO during heating. TSSO containing sesamol, sesamin, and sesamolin showed lower CDA contents and PAV than TSSO without lignan compounds, which suggests that lignan compounds acted as antioxidants in the oxidation of TSSO during heating at 180oC. Decrease in the oxidation of oil during heating was affected by kind and concentration of lignan compounds in the oil and heating time individually and interactively. Addition of sesamol in TSSO at 2,000 ppm showed the highest antioxidant activity and high antioxidant activities of lignan compounds were observed at higher concentration or longer heating time. However, sesamin and sesamolin at 500 and 1,000 ppm concentrations, decreased the TSSO oxidation more than sesamol did. Fatty acid compositions of TSSO were not significantly different among TSSO added with lignan compounds at various concentrations. Lignan compounds contents in TSSO decreased as heating time increased, suggesting their degradation during heating. Degradation rate of sesamol was faster than that of sesamin or sesamolin.
Session 18B, Food Chemistry: Antioxidant and bioactive agents
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |