基于碘量反应电导率变化的食用油过氧化值测定研究  

Determination of Peroxide Value of Edible Oils Based on Electric Conductivity Change during Iodine Reaction

作　　者：杨艳蝶 陈秀梅[1] 于修烛[1] 王亚鸽[1] 

机构地区：[1]西北农林科技大学食品科学与工程学院,陕西杨凌712100

出　　处：《现代食品科技》2013年第12期3053-3058,共6页Modern Food Science and Technology

基　　金：中央高校基本科研业务费专项(QN2013057);陕西省科技攻关项目(2012K02-11)

摘　　要：为了实现简便快速地测定食用油过氧化值,以常见的食用油为原料,基于碘量反应(KI与食用油中的过氧化物反应)导致反应液水相碘离子浓度下降的原理,利用电导率仪测定反应前后水相电导率值,并根据其差值得出食用油过氧化值的变化。通过对检测条件温度、静置时间、振荡时间、饱和碘化钾溶液稳定性和油样种类对测定结果的影响进行研究,建立过氧化值模型并利用国标中碘量法对模型进行验证。结果表明:在室温(25℃)条件下,检测条件对测定结果影响均不显著,建立的食用油过氧化值模型为y=15.05x-0.0327(x为电导率差值,mS/cm;y为过氧化值,mmol/kg),R2=0.9961。模型验证显示模型预测值与国标法测定的过氧化值高度线性相关,R2为0.9981,而且盲样验证相对偏差均小于10%,表明该方法测定食用油过氧化值是可行的。Based on the principle of the decreased ion concentration in aqueous phase resulted from the iodine reaction, the electric conductivity （EC） instrument was used to detect the difference of EC from the reaction solutions thereby PV changes of common edible oils were obtained. The effects of testing temperature, standing time, oscillating time, stability of saturated solution of potassium iodide and types of the oil samples on determination of EC were studied. The PV calibration was established and then validated by iodometry method of Chinese national standards. The results indicated that the experimental conditions had no significant effects on the determination of EC at room temperature （25 ℃）, and the calibration of PV was y=15.05x-0.0327, R2 = 0.9961. The validation suggested that the linear correlativity of the determination of PV between two methods was very well, where R2 was 0.9981, and the relative deviation of blind test was less than 10%. The results indicated that the method was effective to determine PV of edible oil.

关 键 词：碘量反应 电导率 食用油 过氧化值 

分 类 号：TS227[轻工技术与工程—粮食、油脂及植物蛋白工程] O657.1[轻工技术与工程—食品科学与工程]