Classification of cultivation area of ginseng radix with NIR and Raman spectroscopy

Abstract

A rapid and non-destructive method for the classification of ginseng radix according to cultivation area (Korea and China) was evaluated using near infrared (NIR) reflectance spectroscopy. Ginseng samples were collected from widely different growing areas of Korea and China to give more geographical variations. Although there were no obvious differences in the raw NIR spectra based on cultivation area, the spectral features were enhanced and differentiated by utilizing a second-derivative algorithm. Using principal component analysis the cultivation area was clearly differentiated in the principal component space. To develop a classification rule, partial least squares discriminant analysis was carried out. The origin of ginseng was successfully classified and predicted using NIR reflectance spectroscopy combined with discriminant analysis. Additionally, FT-Raman spectroscopy, which provides more qualitative information and easy sample measurement, was also investigated for the same purpose. The results showed that the classification performance using NIR reflectance spectroscopy was superior to that using Raman spectroscopy.