Lipid Oxidation and Antioxidant Changes in Perilla Seeds during Heating

Abstract

Effects of heating conditions and seed roasting on the lipid oxidation and antioxidants of perilla seeds were studied. Perilla seeds, that were unroasted or roasted at 180 o C for 20 min, were ground and heated over steam at 100 o C/ 1 atm or at 135 o C/2 atm. Lipid oxidation was evaluated by peroxide value, conjugated dienoic acids contents, and fatty acid composition. Tocopherols and polyphenols were also determined. Lipid oxidation of perilla seeds was higher during heating at 135 o C/2 atm than at 100 o C/1 atm, and the oxidation rate was lower in unroasted seeds than in roasted seeds. Degradation of tocopherols and polyphenols in perilla seeds during heating was faster under high pressure and temperature, and was decreased by seed roasting. Contribution of polyphenols to the oxidative stability of perilla seeds during heating was higher than that of tocopherols, suggesting polyphenols and seed roasting as important factors in lipid oxidation of perilla seeds. 재료 및 방법 시료의 준비 및 처리

Chemical profiles of heated perilla meal extracts and their antioxidant activities

“…Further heat treatment can transform conjugated chemicals into more soluble or free forms. Wang & Choi (2011) analysed polyphenol compounds and tocopherol in raw and 180 ℃-heated perilla meal. As the heating temperature increased, both phenolic compounds and tocopherol increased in perilla meal.…”