An artificial "tongue" which can taste subtle differences between whiskies could help tackle the counterfeit alcohol trade, according to engineers.
They have built a tiny taster which exploits the properties of gold and aluminium to test differences between the spirits.
The technology can pick up on the subtler distinctions between the same whisky aged in different barrels.
It can tell the the difference between whiskies aged for 12, 15 and 18 years.
Engineers say the tongue "tasted" the differences with greater than 99% accuracy.
Food safety testing
Alasdair Clark, of the University of Glasgow's school of engineering, said: "We call this an artificial tongue because it acts similarly to a human tongue - like us, it can't identify the individual chemicals which make coffee taste different to apple juice but it can easily tell the difference between these complex chemical mixtures.
"We're not the first researchers to make an artificial tongue, but we're the first to make a single artificial tongue that uses two different types of nanoscale metal 'tastebuds', which provides more information about the 'taste' of each sample and allows a faster and more accurate response."
He said the tongue could be used to "taste" virtually any liquid - not just whisky.
Dr Clark added: "In addition to its obvious potential for use in identifying counterfeit alcohols, it could be used in food safety testing, quality control, security - really any area where a portable, reusable method of tasting would be useful."
Whisky was poured over a chequerboard pattern of the two metals - which act as "tastebuds" - and researchers then measured how they absorbed light while submerged.
Subtle differences which were highlighted on the artificial tongue allowed the team to identify different types of the spirit.
The team used the tongue to sample a selection of whiskies from Glenfiddich, Glen Marnoch and Laphroaig.
Research was conducted by engineers and chemists from the universities of Glasgow and Strathclyde.
Their paper, titled 'Whisky tasting using a bimetallic nanoplasmonic tongue', is published in Nanoscale.