基于近红外光谱检测技术鉴别洋槐蜜中掺入大米糖浆的可行性研究

利用近红外光谱技术(near infrared spectroscopy，NIR)并结合化学计量学方法鉴别洋槐蜜中掺入大米糖浆的可行性研究。以来自不同蜂场的20个洋槐原料蜜样品与大米糖浆混合成7个不同浓度梯度(10∶0，9∶1，7∶3，1∶1，3∶7，1∶9，0∶10 g·g-1)共121个样品为研究对象，利用近红外光谱仪和光谱处理软件分别不同浓度梯度的对掺假样品进行光谱扫描和数据转换，并进行主成分分析(PCA)，结合典型判别分析进行区分。结果表明，经过主成分分析后，前2个主成分的得分累计贡献率达97.23%，但掺假样品在第一、第二主成分得分散点图的区域划分不明显。用典型判别分析进一步判别，所有样本均得到准确的判别，准确率为100%，6个典型判别函数中前两个判别函数的累积贡献率达到91.6%，同时在第一类和第二类典型判别函数的分组图中，不同浓度梯度的掺假蜂蜜能够被较好的判别。表明该方法能够快速、有效鉴别大米糖浆在洋槐蜂蜜中的掺假，具有一定可行性和实用性。

Discrimination of Rice Syrup Adulterant of Acacia Honey Based Using Near-Infrared Spectroscopy

At present, the rice syrup as a low price of the sweeteners was often adulterated into acacia honey and the adulterated honeys were sold in honey markets, while there is no suitable and fast method to identify honey adulterated with rice syrup. In this study, Near infrared spectroscopy (NIR) combined with chemometric methods were used to discriminate authenticity of honey. 20 unprocessed acacia honey samples from the different honey producing areas, mixed?with different proportion of rice syrup, were prepared of seven different concentration gradient?including 121 samples. The near infrared spectrum (NIR) instrument and spectrum processing software have been applied in the?spectrum?scanning and data conversion on adulterant samples, respectively. Then it was analyzed by Principal component analysis (PCA) and canonical discriminant analysis methods in order to discriminating adulterated honey , The results showed that after principal components analysis, the first two principal components accounted for 97.23% of total variation, but the regionalism of the score plot of the first two PCs was not obvious, so the canonical discriminant analysis was used to make the further discrimination, all samples had been discriminated correctly, the first two discriminant functions accounted for 91.6% among the six canonical discriminant functions, Then the different concentration of adulterant samples can be discriminated correctly, it illustrate that canonical discriminant analysis method combined with NIR spectroscopy is not only feasible but also practical for rapid and effective discriminate of the rice syrup adulterant of acacia honey.