Introduction
The global alcoholic beverage market is valued at over $1.5 billion and is expected to grow substantially in coming years, making alcoholic beverages a prime target for adulteration. Distilled beverages are normally the most expensive alcoholic beverage per unit mass and they can be adulterated with water, ethanol not meant for human consumption, or the potentially toxic methanol. Likewise, wine can be adulterated with water, artificial sweeteners, or other additives. Misrepresentation of locale or vintage also constitutes adulteration in alcoholic beverages. NIR spectroscopy has been examined for the purpose of determining the presence of adulterants in alcoholic beverages and a summary of one study is presented below.
Analytes
- Products: Whiskey, Brandy, Rum, Vodka
- Adulterants: Water, Ethanol, Methanol
Scientific References and Statistics
Classification of Distilled Alcoholic Beverages and Verification of Adulteration by Near Infrared Spectroscopy – Pontes, Santos, Araujo, et al. Food Research International 39 (2006) 182-189
NIR spectroscopy was examined as a method for classifying alcoholic beverage samples (whiskey, brandy, rum, and vodka) as well as verification of adulteration in the samples. Sixty-nine total samples were used for the study. NIR spectra of the pure samples were collected first. Various samples were then adulterated with 5% and 10% v/v of water, ethanol, or methanol and scanned as well. NIR spectra were collected from 1100 nm to 2500 nm using 2 cm-1 resolution. Sixteen scans were collected and averaged for each spectrum. Principle Component Analysis (PCA) and Soft Independent Modeling of Class Analogies (SIMCA) classification algorithms were used to determine pattern recognition and to characterize each group. The classification models were able to successfully classify at a 100% rate, both for determination of the type of pure sample as well as the presence of an adulterant in any given sample. Verification of the classification was conducted by performing gas chromatography (GC) on samples that were classified as containing an adulterant. The results here can be used as a screening tool to determine the presence of an adulterant in alcoholic beverages and choosing samples which show adulteration for quantitative analysis using a traditional reference method like chromatography.
https://www.sciencedirect.com/science/article/pii/S0963996905001638