The new approach, from Heidelberg University in Germany, takes the form of a so-termed ‘synthetic tongue’. The aim was to develop a method that can tell two closely related whiskies apart to check for quality and to help establish the origins of the product. The ‘tongue’ is in fact an artificial sensor array of such discriminatory power that it can detect whether two nearly identical whisky samples are the same. The sensor arrays are also said, according to Laboratory Manager magazine, to be capable of identifying key qualities like malt status, age, and country of origin.
With the process there are multiple sensors, with each sensor array composed of a series of solutions. Each solution contains a bespoke glowing sophisticated dye. When a droplet of whisky is added into each of the solutions, the addition of the whisky triggers a small change in the brightness of each chemical’s glow. The subtle changes in fluorescence reveal the ‘signature’, in the form of a unique pattern, for each whisky. This is the reason the tongue analogy has been used, since the human tongue has different biological sensors to detect differences between sweet, salty, bitter, sour, umami, and hotness.
According to the principal scientist, Dr. Uwe Bunz: “One of the things I was interested in was ‘how closely related can two analytes be so that you still can tell them apart?’ and for that, whiskies are absolutely fantastic.”
The synthetic “tongues” are effective in drawing similarities between whiskies; however, they cannot identify unknown whiskies from scratch.
The research has been published in the journal Chem, with the research paper titled “A Hypothesis-Free Sensor Array Discriminates Whiskies for Brand, Age, and Taste.”
