采用气相色谱-质谱法, 对掺加6种食用植物油的薄荷油进行快速、有效的鉴定分析.通过检测薄荷油中是否含有植物油的特征成分, 如亚油酸、油酸、棕榈酸、硬脂酸, 可以判断薄荷油样品中是否掺杂植物油. 对6种植物油(豆油、调和油、芝麻油、玉米油、花生油、菜籽油)经甲酯化后的特征成分和共有组分进行分析. 结果表明: 薄荷油经过甲酯化后, 利用植物油的特征峰, 能鉴别出薄荷油中是否掺有植物油, 最低可检出的掺加量为0.001%, 并且根据4种特征脂肪酸峰面积总和与L-薄荷醇峰面积比值, 可以初步推断植物油的掺加水平. 该检验方法灵敏、可靠, 可以为薄荷油的质量安全控制提供重要的技术依据.
A rapid and sensitive method is proposed for determination of peppermint oil adulterated with six edible plant oils using gas chromatography-mass spectrometry (GCMS). With identification of characteristic components of plant oils including linoleic acid, oleic acid, palmitic acid, and stearic acid, it can be determined whether the peppermint oil is spiked with plant oils. Common and special components of six plant oils including soybean oil, blend oil, sesame oil, corn oil, peanut oil, and rapeseed oil are discussed after methyl esterification. The results show that the peppermint oil with more than 0.001% plant oils can be detected. Levels of the adulteration of the plant oils can be obtained based on the peak area ratio between the sum of four kinds of characteristic fatty acid and L-menthol. As a sensitive and reliable method, it provides an effective technique for the quality control of peppermint oil.