‘Artificial tongue’ can detect chemical makeup of alcoholic drinks

Drinks manufacturers and consumers may soon have a small, portable kit, not much bigger than a covid test, to check the quality and safety of alcoholic beverages.

The device is being described as an “artificial tongue” because it can detect additives, toxins and the sweetness of the drink with just a few drops.

Shuo Huang at Nanjing University in China says that while this first generation of the new technology can’t yet test for date rape drugs in spiked drinks or detect methanol contamination, which recently resulted in the deaths of six backpackers in Laos, future versions may.

Current methods for analysing alcoholic drinks, such as liquid chromatography, involve expensive and cumbersome laboratory equipment, requiring expert technicians to operate and analyse samples.

The artificial tongue relies on biological nanopore technology. This uses a modified organism such as a bacterium with a small hole or pore, just a few nanometres in diameter, in its cell membrane. By charging the membrane with electricity, small molecules of the substance being tested can be pulled into and through the pore.

As these molecules pass through the nanopore they create a unique electrical signature, which can be analysed to identify the chemicals present in the sample. Nanopores have already revolutionised DNA sequencing, allowing the almost-instant testing of genetic material with a device that can be easily transported.

Huang and his colleagues used a nanopore already deployed in DNA sequencing, made with a bacterium called Mycobacterium smegmatis.

The device uses artificial intelligence to identify the molecules passing through the nanopore, including flavour compounds and additives, says Huang. “The sensor will immediately tell us what kind of alcoholic beverage it is,” he says. “It can provide a quantitative standard for the product and also easily spot counterfeit alcoholic beverage products as well.”

The nanopore detector only needs a source of electricity to operate, he says. “This nanopore sensing assay can be carried out at home, in the office or by the roadside as well, as simple as a covid test,” Huang says. “The only thing you need to do is to add a drop of alcoholic beverage to the sensor and wait for the result. The machine learning algorithm will do the rest of the job for you.”