New analytical method has a taste for catching counterfeit whiskeys

Whether you pay $50 or $5,000 for your whiskey, it’s safe to say most drinkers of the malted beverage don’t want to get duped into buying—let alone drinking—a counterfeit. An analytical technique that uses fluorescence modulation to discriminate between whiskeys could be a boon to the toolbox of techniques used by the beverage industry to catch fakes (Chem 2017, DOI: 10.1016/j.chem​pr.2017.04.008). The new strategy, which can distinguish whiskeys based on their brand, age, flavor, and region of origin, comes courtesy of Uwe H. F. Bunz of Heidelberg University and colleagues. The team previously developed a similar strategy for identifying white wine varieties. The researchers prepared “artificial tongue” polymer arrays based on 22 fluorescing charged and neutral poly(p-aryleneethynylene)s. They used these polymer arrays to assess 30 whiskeys, including single malts and blends, based on their signature fluorescence patterns created when interacting with the polymers. Three polymers stood out with the highest discriminative power: a positively charged molecule with a perfluorobenzylammonium group and two negatively charged molecules, one bearing carboxylic acid groups and the other equipped with sulfonate groups.