Scottish engineers have developed an artificial “tongue” which can detect subtle differences between the flavours of drams of whisky.
It can differentiate not only between different types of whisky – Glenfiddich, Glen Marnoch and Laphroaig were all tested – but is also capable of picking up on the subtler distinctions between the same whisky aged in different barrels, and tell the difference between the same whisky aged for 12, 15 and 18 years.
The team of scientists from the University of Glasgow behind the project claim the new technology can be used to help cut down on the trade in counterfeit whisky.
They have published their findings in the Royal Society of Chemistry’s Nanoscale journal. They described how they built the tiny taster, which exploits the optical properties of gold and aluminium, to “taste” different drinks.
The artificial tongue’s “tastebuds” are made up of sub-microscopic slices of the two metals, arranged in a checkerboard pattern. The researchers measured how the “tastebuds”, which are 500 times smaller than the human equivalent, absorb light while submerged in the whisky.
Statistical analysis of the very subtle differences in how the metals in the artificial tongue absorb light – what scientists call their plasmonic resonance – allowed the team to identify different types of whiskies with greater than 99% accuracy.
Dr Alasdair Clark, of the University of Glasgow’s School of Engineering and the paper’s lead author, 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.
“While we’ve focused on whisky in this experiment, the artificial tongue could easily be used to ‘taste’ virtually any liquid, which means it could be used for a wide variety of applications. 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.”