First, it was the wine drinkers (my July 28, 2011 posting titled: Bio-inspired electronic tongue replaces sommelier? about research performed by Spanish researches at the UAB (Universitat Autònoma de Barcelona) now, these researchers have turned their attention to beer. From a Jan. 30, 2014 news release on EurekAlert,
Beer is the oldest and most widely consumed alcoholic drink in the world. Now, scientists at the Autonomous University of Barcelona have led a study which analysed several brands of beer by applying a new concept in analysis systems, known as an electronic tongue, the idea for which is based on the human sense of taste.
As Manel del Valle, the main author of the study, explains to SINC [Spain's state public agency specialising in science, technology and innovation information]: “The concept of the electronic tongue consists in using a generic array of sensors, in other words with generic response to the various chemical compounds involved, which generate a varied spectrum of information with advanced tools for processing, pattern recognition and even artificial neural networks.”
In this case, the array of sensors was formed of 21 ion-selective electrodes, including some with response to cations (ammonium, sodium), others with response to anions (nitrate, chloride, etc.), as well as electrodes with generic (unspecified) response to the varieties considered.
The authors recorded the multidimensional response generated by the array of sensors and how this was influenced by the type of beer considered. An initial analysis enabled them to change coordinates to view the grouping better, although it was not effective for classifying the beers.
“Using more powerful tools – supervised learning – and linear discriminant analysis did enable us to distinguish between the main categories of beer we studied: Schwarzbier, lager, double malt, Pilsen, Alsatian and low-alcohol,” Del Valle continues, “and with a success rate of 81.9%.”
It seems the electronic tongue does have one drawback,
Furthermore, it is worth noting that varieties of beers that the tongue is not trained to recognise, such as beer/soft drink mixes or foreign makes, were not identified (discrepant samples), which, according to the experts, validates the system as it does not recognise brands for which it was not trained.
Future plans, according to the news release, include,
In view of the ordering of the varieties, which followed their declared alcohol content, the scientists estimated this content with a numerical model developed with an artificial neural network.
“This application could be considered a sensor by software, as the ethanol present does not respond directly to the sensors used, which only respond to the ions present in the solution,” outlines the researcher.
The study concludes that these tools could one day give robots a sense of taste, and even supplant panels of tasters in the food industry to improve the quality and reliability of products for consumption.
Here’s a link to and a citation for the paper,
Beer classification by means of a potentiometric electronic tongue by Xavier Cetó, Manuel Gutiérrez-Capitán, Daniel Calvo , and Manel del Vall. Food Chemistry Volume 141, Issue 3, 1 December 2013, Pages 2533–2540 DOI: 10.1016/j.foodchem.2013.05.091
I’d imagine that anyone who has dreams of becoming a beer taster might want to consider some future alternatives. As for folks like Canadian Kevin Brauch, “host of The Thirsty Traveler [on the Cooking Channel], … about the world’s greatest beer, wine and cocktails,” he will no doubt claim that a robot is not likely to express like/dislikes or more nuanced opinions, should he become aware of his competitor. Besides, Brauch does have the cocktail to rely on; there’s no word of cocktails being test on an electronic tongue, not yer.
Historically, Canada has been a beer drinkers nation. According to data collected in 2010, we rank fifth in the world (following the Czech Republic, Germany, Austria, and Ireland, in that order) found in the Wikipedia essay: List of countries by beer consumption per capita. For anyone who’s curious about Canadian beer drinkers’ perspectives, I found this blog, The Great Canadian Beer Snob (as of 2012 the blog owner, Matt Williams lived in Victoria, BC), which I suspect was a name chosen with tongue-in-cheek.