Electronic “tongues” or e-tongues have been the focus of research for several years, with applications for sampling wine, screening for bacteria and contamination in production, distinguishing between different varieties of beer, or evaluating milk and dairy products. The National Science Foundation recently awarded a $50,000 grant to the University of Massachusetts Lowell for continued development of an e-tongue to test water and beverages for lead, cadmium, mercury, and arsenic, as well as heavy metals such as chromium, nickel, copper, and zinc.
The technology being developed at the university was invented by Pradeep Kurup in the department of civil and environmental engineering, and it is expected to be faster, more cost effective, less invasive, and easier to use for food safety applications and environmental monitoring than traditional and current methods, according to information released by the university.
Another team of researchers in the Ukraine and France reported this fall in ACS Applied Materials & Interfaces about their work on an electronic tongue with a silicon base that can be incorporated into existing systems of the same material. This method is based on intrinsic sensitivity of the silicon surface to the liquid being tested and allows for creation of the liquid’s characteristic electronic fingerprints that mimic how tastes are perceived by humans, according to S.V. Litvinenk at Taras Shevchenko National University of Kyiv, and colleagues. “To increase recognition reliability, a set of characteristic fingerprints for a given liquid/silicon interaction” is recorded at different bias voltages, the researchers said.
The team hopes that their invention can also be applicable for testing food safety and quality. The researchers report that they have tested Armagnac, cognac, whiskey, and water, and that the e-tongue system was able to establish electronic fingerprints of each. Further applications, they say, could include medical diagnostics, pharmaceutical testing, and environmental monitoring.
Another team working on development of an electronic tongue for food safety reported earlier this year in Chemosensors (doi:10.3390/chemosensors2040251) their invention of a voltammetric e-tongue that detects harmful substances intentionally added to milk to increase its shelf life or to imitate protein content. The researchers from Brazil demonstrated that their process could discriminate contamination of milk with urea, formaldehyde, and melamine. “The proposed electronic tongue has great potential for differentiating between adulterations in a wide variety of milk,” they said.