摘要
建立植物类油脂(食用植物油及地沟油)中胆固醇含量测定的气相色谱-质谱联用测定方法。食用植物油及地沟油样品中加入40 mL 2.0 mol/L的氢氧化钾溶液,85℃水浴中加热皂化60 min,经二氯甲烷萃取、浓缩后,经HP-5MS石英毛细管柱分离,用气相-质谱联用仪采用选择离子扫描方式测定,外标标准曲线法进行定量。利用方法,胆固醇在0.5 mg/L^50 mg/L质量浓度范围内与峰面积呈良好的线性关系,相关系数r2为0.999 3,方法检测限为1.0 mg/kg。在3个浓度水平下对大豆油进行加标回收试验,测得平均回收率在90.2%~95.5%,相对标准偏差为2.7%~4.7%。该法操作简便、重现性好、准确度高,适用于各种植物类油脂中胆固醇含量的定量测定,检测结果可作为鉴别植物类油脂中是否掺有地沟油的依据之一。
A method for the determination of cholesterol in vegetable oils （edible vegetable oil and drainage oil） by GC-MS was proposed. The edible vegetable oil and drainage oil sample were saponified with 2.0 mol/L KOH 40 mL, 85 ℃ water bath heating, 60 min, the extracted with dichloromethane. After separated by the HP-5MS quartz capillary column, the samples were detected by GC-MS under selected ion mode, with the external standard method. Linearity range was found between 0.5 mg/L and 50 mg/L, the relative of coefficient was 0.999 3, and detection limit （3S/N） was 0.01 mg/L. The average recoveries of soybean oil was tested at 3 concentration levels and values of recovery found were in the range from 90.2% to 95.5% with relative standard deviations（RSD） of 2.7% - 4.7%. The method was simple, sensitive, accurate and the detection result can be one of the criteria judging the existence of drainage oil in edible vegetable oil.
出处
《食品工业》
北大核心
2014年第8期259-261,共3页
The Food Industry
基金
国家自然科学基金(21171097)
江苏省高校自然科学研究项目(13KJD150001)
南京晓庄学院科研项目(2012NXY18)
关键词
胆固醇
气相色谱-质谱
地沟油
cholesterol
gas chromatography-mass spectrometry（GC-MS）
drainage oil
