Diners in Japan could soon be able to savour the umami of a bowl of ramen or miso soup without having to worry about their salt intake.
In what they claim is a world first, researchers have developed chopsticks that artificially create the taste of salt, as part of efforts to reduce sodium levels in some of the country’s most popular dishes.
The chopsticks work by using electrical stimulation and a mini-computer worn on the eater’s wristband.
The device transmits sodium ions from food, through the chopsticks, to the mouth where they create a sense of saltiness, according to Homei Miyashita, a professor at Meiji University in Tokyo, whose laboratory collaborated with the food and drink manufacturer Kirin to develop the device.
The team said they would refine the prototype and hoped to make the chopsticks available to consumers next year.
The utensils could find a receptive audience in Japan, where the traditional diet tends to be high in salt due to the use of ingredients such as miso and soy sauce.
The average Japanese adult consumes about 10 grams of salt a day, double the amount recommended by the World Health Organization. The health ministry has proposed reducing daily salt intake to a maximum of 7.5 grams for men and 6.5 grams for women.
The chopsticks use “very weak electricity – not enough to affect the human body – to adjust the function of ions such as sodium chloride and sodium glutamate to change the perception of taste by making food seem to taste stronger or weaker”, Kirin said in a statement.
Miyashita and Kirin said clinical tests on people who follow a low-sodium diet had confirmed that the device enhances the salty taste of low-sodium food by about 1.5 times. They said participants given reduced-salt miso soup had commented on the improved “richness, sweetness and overall tastiness” of the dish.
High salt intake can contribute to high blood pressure, which is the single biggest cause of heart attacks and strokes.
“To prevent these diseases, we need to reduce the amount of salt we take,” said Kirin researcher Ai Sato. “If we try to avoid taking less salt in a conventional way, we would need to endure the pain of cutting our favourite food from our diet, or endure eating bland food.”
Miyashita’s lab is exploring other ways in which technology can be used to engage the senses – it has also invented a lickable TV screen that imitates the flavours of various foods.