Indian experts devise simple test to detect fake Scotch

Three physicists at the University of St Andrews have devised a laser test to detect counterfeit Scotch and single malt whiskies, raising the possibility of clamping down on the fake liquor industry in India and elsewhere.

It is often remarked in Scotch whisky industry circles that more 'Scotch' is produced and sold in India than is produced in Scotland.

However, the Indian origin experts say the genuine Scotch one can be detected from the fake by using the power of lasers. Their research has been published in the journal Optic Express.

Using a ray of light the size of a human hair, the novel method can work out the brand, age and even which cask was used to create a single malt, from a sample no bigger than a teardrop, a university release said.

The research, which has been patented and is being presented to industry, was carried out by physicists Praveen Ashok, Kishan Dholakia and Bavishna Praveen.

Praveen explained: "Counterfeiting is rife in the drinks industry, which is constantly searching for new, powerful and inexpensive methods for liquor analysis. Using the power of light, we have adapted our technology to address a problem related to an industry which is a crucial part of Scottish culture and economy."

The research involves researchers placing a tiny amount of whisky on a transparent plastic chip no bigger than a credit card. Using optical fibres the width of a human hair, the whisky sample is illuminated by light using one fibre, and collected by another.By analysing the collection of light scattered from the whiskey, the researchers are able to diagnose the sample.

The key lies in the fact that the laser can detect the amount of alcohol contained in the sample – genuine whiskey must contain at least 40 per cent, the release added.

The method exploits both the fluorescence of whisky and the scattering of light and shift in energy when it interacts with molecules (known as its 'Raman signature').

Ashok said: "Whisky turns out to be very interesting: we can not only gather information about the alcohol content, but also the colour and texture. These are dictated by the manufacturing process, which of course influences greatly the type of whisky people enjoy".

The chip used in the study was originally employed in the detection of bio-analytes by the group in biomedical studies.

Dholakia added: "Light is incredible and has led to amazing advances in the last fifty years since the advent of the laser. It is amazing to think that the technology we are developing for biomedical analysis can also be used to help us enjoy a wee dram – and with the minimum of waste."