This Electronic 'Tongue' Can Ensure Food Quality
An electronic tongue can now sample food, testing for bacteria and other contamination during production or transport, as well as drive new procedures in medicine. The same system could also, one day, examine water supplies, examining supplies for toxic, potentially hazardous, contaminants. Medical technology could benefit, as blood samples could be studied by the device.
Human tongues were used as the model for the new generation of the electronic system. Researchers wanted an artificial tongue that would react in much the same way as a human organ.
Food producers and the service industry are already making use of the new technology, both to ensure safety, as well as to test the taste of their products.
"S. V. Litvinenko and colleagues explain that an electronic tongue is an analytical instrument that mimics how people and other mammals distinguish tastes. Tiny sensors detect substances in a sample and send signals to a computer for processing just as taste buds sense and transmit flavor messages to the brain," the American Chemical Society explained in a press release.
The e-tongue utilizes a base of silicon, allowing the device to easily be integrated in existing electronic equipment, used to process the data collected by the mechanism. The device is layered with a liquid analyte (the carrier of the material being measured) above the silicon base, covered by a glass layer. Measurements are made through the use of a radio frequency (RF) emitter and detector.
Changes in the silicon base provide the raw data , measuring the contents of the analyte being measured, providing a unique chemical "fingerprint" of each component of the sample.
Testing equipment used previously to this new development was limited, as they could not respond to tastes in food and drink in the same manner as human tongues.
Whiskey, cognac, Armagnac, and water were each sampled by researchers using the e-tongue, and the device was able to differentiate between each of the liquids.
Human tongues contribute, along with smell, to the sensation of taste through taste receptors. Most e-tongues use seven main varieties of electronic taste buds. In people, electrical signals sent through the nerves travels to the brain, where they are processed into taste. Sensors in the e-tongue send similar electronic signals through the silicon base, for processing by external processors.
This is not the first e-tongue, but it is designed to be more versatile than earlier versions.
An electronic tongue that could distinguish between different brands of beer was announced in January 2014, developed by researchers in Spain. That design of e-tongue was accurate 82 percent of the time in tests.
Development of the electronic tongue was profiled in the journal ACS Applied Materials & Interfaces.