Classification of illicit liquors based on their geographic origin using Attenuated total reflectance (ATR) - Fourier transform infrared (FT-IR) spectroscopy and chemometrics.

In recent decades vibrational spectroscopy especially infrared (IR) spectroscopy has emerged as a fast, sensitive, and reliable technique in classifying alcoholic beverages based on geographic origin. However, Attenuated total reflectance (ATR) - Fourier transform infrared (FTIR) spectroscopy has not been used in many studies. In the present study, an attempt has been made to classify 75 samples of illicit liquor from different regions of India based on their geographical origin. The samples were scanned in the MIR range of 600-3000cm-1. It was observed that while using PCA 76% accuracy was obtained and while using LDA 93% accuracy was obtained. The samples of Delhi, Mansa, Patiala, Pathankot, and Fatehgarh Sahib show 100% classification with LDA whereas the samples from Ferozpur and Gurdaspur showed a 75% correct classification. These results point out toward the potential applicability of ATR-FTIR for the classification of alcoholic beverages based on the geographic origin.