摘要
寻找地沟油中的特异性指标,根据其量值高低识别食用油和地沟油。实验采取两种路径:一是样品经皂化、甲酯化后分析脂肪酸类成分;二是直接采用顶空进样富集样品中的挥发性成分,然后采用气相色谱-质谱法分析各化学成分的量值规律。研究发现,棕榈油酸与异丁烯醛在地沟油中特异性较强。在所测定样本中,以棕榈油酸单独鉴别时,总体检出正确率为54.1%,阳性样本检出正确率为100.0%、漏检率为60.7%,阴性样本检出正确率为100.0%;以异丁烯醛单独鉴别时,总体检出正确率为78.4%,阳性样本检出正确率为100.0%、漏检率为28.6%,阴性样本检出正确率100%。二者协同鉴别,总体检出正确率为86.5%,阳性样本检出正确率为100.0%、漏检率为17.9%,阴性样本检出正确率100.0%。棕榈油酸和异丁烯醛作为鉴别地沟油的特异性指标,两项检测结果能够相互印证、综合判断,可较为准确地分辨地沟油和食用油。
This study was conducted to find out specific indicators for discriminating drainage oil from edible oil. For this purpose, tow approaches were proposed: one was analysis of fatty acid composition following sample saponification, and the other was methyl esterification and direct enrichment by headspace sampling method and GC-MS analysis of volatile components in samples. Results revealed that palmitoleic acid and methacrolein showed strong specificity in drainage oil. In the studied samples, using palmitoleic acid alone for identification, the overall correct detection rate was 54.1%, the correct detection rate of positive samples was 100%, the false negative rate was 60.7%, and the correct detection rate of negative samples was 100%. When using methacrolein along, the overall correct detection rate was 78.4%, the correct detection rate of positive samples was 100% and the false negative rate was 28.6%, and the correct detection rate of negative samples was 100%. However, when combining palmitoleic acid and methacrolein together, the overall correct detection rate was 86.5%, the correct detection rate of positive samples was 100%, the false negative rate was 17.9% and the correct detection rate of negative samples was 100%. Therefore, the combined application of palmitoleic acid and methacrolein were proposed as specific indicators in differentiating drainage oil. The two-way methods could be mutual validated, of overall judgment, and identify the drainage oil and the edible oil more accurately.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2013年第8期199-203,共5页
Food Science
基金
陕西省科学技术研究发展计划项目(2011K17-05-04)
陕西省食品药品检验所青苗基金项目(SQM-201005)
关键词
地沟油
食用油
棕榈油酸
异丁烯醛
气相色谱-质谱法
drainage oil
edible oil
palmitoleic acid: methacrolein
gas chromatography-mass spectrometry