Past studies have described how introducing a weak electrical current to the tongue can affect the charged ions that make up sodium chloride to either inhibit or enhance saltiness and other taste sensations.
With this in mind, researchers at Meiji University and Japanese food and beverage company Kirin designed a chopstick-like device that uses a weak electrical charge to stimulate how the tongue experiences saltiness.
They then gently zapped their own taste buds before testing the effects of the electrified chopsticks in an experiment involving 31 people previously or currently on a low-sodium diet.
Each person tasted and rated the saltiness of several saltwater gel samples that had two different levels of saltiness. The results showed that electric stimulation enhanced the saltiness of the low-sodium sample, making it comparable to the control sample, which was 40% or more saltier. In other words, electrified chopsticks or other utensils could reduce salt intake by 30% without sacrificing saltiness.
The discomfort caused by electrical stimulation was not severe enough to be a problem for most participants. More than 80% of subjects said they could tolerate the electric stimulation on a daily basis.
Electrical stimulation of the tongue through a chopstick-shaped utensil may even potentially enhance the savouriness of low-sodium food, the scientists claimed.
In a second qualitative experiment, the participants consumed a low-sodium miso soup, which many found had a better mouthfeel and taste, suggesting that electric taste stimulation may also affect umami, according to the paper. Umami is a fifth sensory taste often described as savouriness.