3种抗氧化剂对菜籽油氧化稳定性的影响

Effect of three antioxidants on oxidative stability of rapeseed oil

为探究抗坏血酸棕榈酸酯、迷迭香提取物和茶多酚棕榈酸酯及其复合物对菜籽油氧化稳定性的影响,采用Schaal烘箱加速氧化实验法对菜籽油进行氧化稳定性评价,并采用响应面实验优化复配抗氧化剂的配方。结果表明:3种抗氧化剂均能显著提高菜籽油的氧化稳定性(P<0.05),其中茶多酚棕榈酸酯抗氧化效果最为理想,添加量为0.01%和0.05%时,菜籽油过氧化值比空白对照分别降低了61.76%和68.79%;响应面实验得到最优复配抗氧化剂配方为0.02%抗坏血酸棕榈酸酯、0.03%迷迭香提取物、0.03%茶多酚棕榈酸酯,在此配方下加速氧化13 d时菜籽油过氧化值为6.017 mmol/kg。该复配抗氧化剂能有效减缓菜籽油的氧化速度,且能够保护菜籽油不易受高浓度抗氧化剂的促氧化作用。

In order to explore the effects of ascorbyl palmitate, rosemary extract, tea polyphenol palmitate and their compounds on the oxidative stability of rapeseed oil, the Schaal accelerated oxidation test method was used to evaluate the oxidative stability of rapeseed oil, and the response surface methodology was used to optimize the formula of the compound antioxidant. The results showed that three antioxidants could significantly improve the stability of rapeseed oil(P<0.05), and the antioxidant effect of tea polyphenol palmitate was the best. When 0.01% and 0.05% of tea polyphenol palmitate were added, the peroxide value of rapeseed oil was 61.76% and 68.79% lower than that of the control, respectively. The optimal formula of compound antioxidant was obtained as follows: ascorbyl palmitate 0.02%, rosemary extract 0.03%, tea polyphenol palmitate 0.03%. The peroxide value of rapeseed oil added by compound antioxidant with optimal formula was 6.017 mmol/kg after accelerated oxidation for 13 d. The compound antioxidant could effectively slow down the oxidation rate of rapeseed oil, and could protect rapeseed oil from the pro-oxidation effects of high concentrations antioxidants.