Electronic tongue develops a taste for brandy


© Shutterstock

When it comes to brandy, analysis is an important part of the production process. It's usually carried out by a panel sense experts, but now a team of Spanish scientists is set to replace the human palate with an electronic tongue that classifies brandy according to taste, and can even discriminate between aging methods.

An electronic tongue is an analytical system that mimics the sense of taste using an array of sensors and advanced signal-processing methods. Where classical analytical chemistry involves the identification of individual chemical species, an electronic tongue creates a fingerprint using multiple signals from its sensor array. This is useful for looking at alcoholic beverages, in which the species responsible for specific tastes are often unknown.

Electronic tongues have been used successfully to analyse beer, wine and whisky, and now Manel del Valle, from the Autonomous University of Barcelona, Spain, and colleagues have applied the technique to brandy. The team set about assembling a set of six voltammetric sensors, each prepared with different modifiers – metallic nanoparticles, conducting polymers or redox catalysts. Every sensor gave a response to every sample, but in a slightly different way. These responses were combined and treated with data-processing tools before the system was ‘trained’ to classify brandies using a set of human-evaluated samples as a reference.

‘In essence,’ explains del Valle, ‘we are translating expertise from these human testers to a sensor-based analytical system.’

The electronic tongue was found to be 100% accurate when classifying brandy samples according to their taste attributes, and also performed well in the discrimination of different ageing methods and vintages. A further computational model was then constructed for the semi-quantitative detection of undesirable compounds known to cause taste defects. Such information could be invaluable in quality-control processes.

‘This work is a neat illustration of the power of robust computational methods for classification,’ remarks Osvaldo Oliveira, an expert in electronic-tongue systems from the University of São Paulo, Brazil. ‘The classification methods are entirely generic and can be extended to other types of sensor,’ he says, hinting at the application of the technology to the detection of substances that cause food poisoning.

Indeed, del Valle and his colleagues plan to continue their collaborations with the food and beverage industries, and are beginning  to look at analytical methods related to security applications.

References

X Cetó et al, Anal. Methods, 2013, 5, 1120 (DOI: 10.1039/C2AY26066B)


Related Content

Chemistry World podcast - April 2013

4 April 2013 Podcast | Monthly

news image

Geoffrey Kibby on mushroom chemistry, Paul Midgley illuminates 3D imaging and the team cover the latest news

Lab-on-a-chip rises to cola challenge

13 May 2013 Research

news image

'Liquid fingerprinting' can 'taste' the difference between red wines, mineral waters and vodkas

Most Read

Higher levels of some metals in e-cigarette smoke

8 September 2014 Research

news image

Scientists call for regulators to help clear smoke and mirrors surrounding vaping safety

Isotope effect produces new type of chemical bond

22 October 2014 Research

news image

Evidence emerges for vibrational bond first proposed 30 years ago

Most Commented

Higher levels of some metals in e-cigarette smoke

8 September 2014 Research

news image

Scientists call for regulators to help clear smoke and mirrors surrounding vaping safety

US agency fast-tracks Ebola vaccine development

23 October 2014 News and Analysis

news image

Health and Human Services invests almost $6 million to ready an Ebola vaccine candidate for clinical trials, meanwhile GSK sa...