The five taste chemicals, which can be mixed before delivery, correspond to those detected in the original consumable item: glucose, which creates a sweet sensation; citric acid, which produces a sour taste; sodium chloride, which generates a salty flavour; magnesium chloride, a bitter taste; and glutamate, which elicits the savoury taste known as umami.
Despite previous attempts by some researchers, the team behind the new study notes that there are numerous hurdles, not least that directly stimulating the tongue electronically or with warmth only enables a few tastes to be evoked; the use of chemicals can pose problems for reliability; and the arrangement of tastebuds on the tongue means it is necessary to target particular areas to create particular sensations.
In another test six volunteers were asked to sample different combinations of liquids containing the flavour chemicals, with the combinations designed to represent five different edible items – lemonade, cake, fried egg, coffee, and fish soup.
The first is a sensing platform – or “electronic tongue” – that captures data about the concentration of five different taste chemicals in a liquidised sample of a food or drink and sends the information wirelessly to the second component.
This device uses small electromagnetic pumps to push liquids through a layer of gel containing five edible taste chemicals, allowing their delivery to an outlet, placed in a recipient’s mouth, to be controlled.
