Rapid detection of patchouli oil mixed by coconut oil using NIRS technology and chemometrics method

Aceh patchouli oil is sometimes mixed with various oils for profit resulting in the low quality of patchouli oil. This low quality caused Aceh patchouli oil to depress its selling price. The main objective of this study is to develop NIRS technology to investigate the authenticity of patchouli oil mixed with coconut oil using Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) methods. This present study uses 6 kinds of sample treatment namely pure oil and mixed oil with a total of 42 samples for calibration and 18 samples for validation. The results showed that NIRS Technology with PCA and LDA methods provides a solution opportunity to solve the problem of counterfeiting patchouli oil with coconut oil. The PCA method successfully obtained a classification model that was able to provide a clear visual appearance to distinguish between pure patchouli oil and a mixture of patchouli oil and coconut oil. Meanwhile, the LDA method successfully obtained a validated classification model with the number of errors 1 out of 18 independent validation samples to distinguish between pure patchouli oil and non-patchouli oil.