基于稀土元素含量鉴别浙江省山茶油产地

Identification of camellia oil producing area in Zhejiang province based on the rare earth elements content

目的测定浙江省绍兴、丽水、金华、温州、杭州和衢州6个主产区的121份茶油中16种稀土元素含量,通过建立判别模型,对茶油的原产地进行鉴别。方法基于电感耦合等离子体质谱(inductively coupled plasma source mass spectrometer, ICP-MS)测定油茶16种稀土元素含量,并对不同地区油茶中稀土元素含量差异进行分析比较。结果 16种稀土元素总含量在560.0～1560.0 ng/kg之间,不同地区茶油样品中Y、La、Ce、Pr、Eu、Dy、Ho、Er、Tm、Yb、Lu和Th等元素在浙江省内不同地区差异较大(P<0.05)。茶油中多种稀土元素包含的信息能够反映出元素分布与茶油来源的关系。通过判别分析表明,浙江省不同地区茶油样品判别正确率为76.9%～96.4%,交叉验证判别正确率为72.4%～96.4%。结论茶油中稀土元素含量较低,基于稀土元素结合判别分析能够有效鉴别浙江不同地区茶油产地来源。本研究可从一定程度上填补对茶油中稀土元素含量研究和茶油产地判别的空缺,也为其他木本油料的产地鉴别研究提供参考。

Objective To determine the content of 16 kinds of rare earth elements in 121 camellia oil samples from Shaoxing, Lishui, Jinhua, Wenzhou, Hangzhou and Quzhou in Zhejiang province, and identify the country of origin of camellia by establishing the discriminant model. Methods The content of Ce, Dy, Er, Eu, Gd, Ho, La, Lu, Nd, Pr, Sc, Sm, Tb, Tm, Y, Yb was determined and analyzed by inductively coupled plasma mass spectrometry(ICP-MS). The content of rare earth elements in Camellia oleifera in different areas was compared. Results The total content of 16 rare earth elements ranged from 560.0-1560.0 ng/kg. The content of Y, La, Ce, Pr, Eu, Dy, Ho, Er, Tm, Yb, Lu and Th of camellia oil samples from different regions had significant differences(P<0.05). The information of rare earth elements in camellia oil could reflect the relationship between element distribution and camellia oil source. The linear discriminant analysis showed that the correct classification rates of the camellia oil samples from different regions were 76.9%-96.4%, and the cross validation accuracy of discrimination were 72.4%-96.4%. Conclusion It can be found that the content of rare earth elements in tea oil is in relatively low level. Combined discriminant analysis based on rare earth elements can effectively identify the tea oil sources in different areas of Zhejiang. To some extent, this study can fill the gap in the study of rare earth element content in camellia oil and the identification of camellia oil origin, and also provide reference for the identification of other woody oil origin.