电化学分析法同时测定植物油中的抗氧化剂TBHQ和VE  

Simultaneous Determination of TBHQ and VE in the Vegetable Oil with Electrochemical Method

作　　者：李书国[1] 袁涛[1] 王丽然[1] 

机构地区：[1]河北科技大学食品科学系,石家庄050018

出　　处：《中国粮油学报》2013年第5期90-95,共6页Journal of the Chinese Cereals and Oils Association

基　　金：国家自然科学基金面上项目(20876165)

摘　　要：采用循环伏安法对抗氧化剂TBHQ(特丁基对苯二酚)和VE(生育酚)在有机相中的电化学氧化反应机理进行了研究,TBHQ氧化峰电位为800 mV,VE氧化峰电位为640 mV;优化了电化学法测定2种抗氧化剂的试验条件,选定有机溶剂为含6 mmol/L硫酸的1,4-二氧六环-乙腈(3:1;V/V)溶液,支持电解质是0.03 mol/L氯化锂;在优化条件下,以微分脉冲伏安法测定TBHQ和VE的线性范围分别是4.0×10-5～5.5×10-4 mol/L和2.0×10-5～7.0×10-4 mol/L,检测限分别是1.5μmol/L和1.6μmol/L,线性系数分别是0.998和0.997。由于2种抗氧化剂的伏安波谱峰有部分重叠,常规方法难以准确其各自含量水平,因此采用偏最小二乘法(PLS)对波谱进行解析,并用该法对实际油样进行测定,回收率为97.7%～104.2%;结果表明该法在有机相中同时测定植物油中的TBHQ与VE是可行的,不需预处理,油样需要量少,方法简便快捷。Cyclic voltammetry was adopted for the electrochemical oxidation mechanism of antioxidant TBHQ and VE in organic phase. Cyclic vohammogram of these two compounds exhibited two well - defined oxidation wave peaks at 800 mV ,640 mV potential for TBHQ and VE respectively. The electrochemical conditions were optimized to determine two kinds of antioxidants. The selected organic solvent was 1,4 -dioxane -acetonitrile （3： 1, V/V）including 6 mmol/L sulphuric acid, and the supporting electrolyte was 0.03 mol/L lithium chloride. In the optimized condi- tions,the calibration curves for the determination of TBHQ and VE demonstrated an excellent linear response in the range from 4.0 × 10 ^-5 to 5.5 ×10 ^-4 mol/L and from 2.0× 10^ -5 to 7.0 × 10 ^-4 mol/L for two compounds respectively depending on the differential pulse vohammetry. Detection limits and linear coefficient in the range were obtained, 1.5 x 10-6 molL^-1 and 1.6 ×10^-6 mol/L,0. 998 and 0. 997 for TBHQ and VE respectively. The vohammograms of these two compounds were overlapped, so quantitative analysis for each of these antioxidant compounds in a mixture was investigated with the aid of partial least squares （PLS）. The proposed method was successfully applied in the simultaneous determination of TBHQ and VE in several oil samples. The recovery varied from 97.7% to 104.2%. The developed method was practicable in the simultaneous determination of TBHQ and VE in vegetable oils, simply and rapid without any pretreatments.

关 键 词：有机相 电化学 抗氧化剂 偏最小二乘法 

分 类 号：TS225.1[轻工技术与工程—粮食、油脂及植物蛋白工程]