Laser tech detects fake alcohol bottles non-invasively

Methanol poisoning from contaminated alcohol is relatively rare in countries with strict alcohol regulation, but it remains a serious problem in regions where counterfeit alcohol is common. Outbreaks continue to occur every year, causing deaths, blindness, and permanent injuries. A few years ago in Laos, six foreign tourists died after drinking at a backpacker hostel, and an even bigger outbreak occurred in Turkey in 2025, taking the lives of 160 people and leaving more than 250 incapacitated. Both cases were attributed to methanol poisoning from illegally produced alcohol.The scariest part is how little of this chemical can cause such severe damage. Just 10 mL of methanol (two teaspoons) can cause permanent blindness and kidney failure, while a larger dose can be fatal.There are three main types of alcohol that we all encounter in everyday life: ethanol, found in alcoholic beverages, isopropyl alcohol, used as a disinfectant and cleaning agent, and methanol, an industrial chemical used in windshield washer fluid, antifreeze, and solvents. Only ethanol is safe to drink, but some counterfeit producers may dilute it with methanol. It happens for several unethical reasons: methanol mimics a higher alcohol content, it’s not taxable like drinkable alcohol, and it’s simply cheaper and can increase profits.Legitimate alcohol manufacturers use strict quality controls, and all their products undergo extensive testing, which is expensive and takes quite a bit of time. Conducting those tests without opening the bottle and sending a sample to a laboratory was impossible until a recent discovery made by scientists from the University of St. Andrews in Scotland and Adelaide University in South Australia.The researchers used a technology called Raman spectroscopy to read what they call “the unique chemical fingerprint of a liquid.” Here is how it works.A laser beam is directed into a liquid, and scientists analyze how the light is scattered when it hits the surface and excites the molecules of the liquid. Those distinct patterns are what tell us the liquid's chemical composition.By carefully shaping the laser beam and changing its wavelength, the researchers were able to filter out interference from the bottle itself. This is why this particular method of testing doesn’t require the bottles to be opened, which is the biggest breakthrough.The research team was able to detect methanol in whiskey at concentrations around 10 times lower than internationally recognized safety standards. On top of being extremely reliable, this technology is also cheaper and faster than traditional laboratory testing, so it could become a real weapon against fake alcohol worldwide.Big wine producers like Australia could benefit a lot from this technology, given that wine fraud costs the global industry billions of dollars every year. But this approach has huge potential far beyond alcohol production. The researchers hope that in the future it will be used to identify counterfeit perfumes, detect pesticide contamination in olive oil, and offer better quality control across agriculture in general.This new technology is primarily aimed at large organizations such as customs agencies, alcohol producers and distributors, and food safety authorities. While it could reduce the risk of counterfeit alcohol reaching store shelves, consumers still remain vulnerable. Avoiding suspiciously cheap alcohol and poorly labelled products is still a good defense strategy.Source: Adelaide University