Japanese scientists develop ‘smart’ chopsticks to add salty flavour to food

In a bid to reduce sodium consumption, scientists in Japan have invented a pair of chopsticks that artificially create the taste of salt. 

The innovative solution has been developed by staff at Meiji University in Tokyo and beverage manufacturer Kirin, who say the invention is a world first. 

To use the chopsticks, diners wear a wristband which contains a mini-computer. The device transmits sodium ions from the food, through the chopsticks and then to the mouth where they create the salty flavour. 

The device utilises a weak electrical current to transmit sodium ions to the eater. According to Meiji University professor and co-designer of the chopsticks Homei Miyashita, the technology enhances the salty taste up to 1.5 times. 

This claim was reaffirmed in testing, according to Miyashita and Kirin. They said participants given a reduced-salt miso commented on the improved “richness, sweetness and overall tastiness” of the soup. 

It is thought the chopsticks could become particularly revered in Japan, where traditional eating habits favour saltier ingredients and dishes like soy sauce, miso and ramen. 

The average Japanese adult consumes around 10g of salt a day, which is double the amount recommended by the World Health Organisation.

The impacts of a diet high in salt are well documented. Excess sodium intake is linked to higher blood pressure, which in turn can lead to heart disease and stroke. 

“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 and his lab have a history of projects which explore how technology can interact with and stimulate human sensory experiences. 

In 2021, he unveiled a ‘lickable’ television screen which imitates food flavours in correspondence to what is shown on screen. Miyashita also developed a fork which used a similar technology to his chopsticks and made food taste richer. 

Miyashita and Kirin’s invention is one of a growing number of products which aim to replicate the taste of HFSS foods, without the negative health impacts, using technology which plays with the senses. 

German start-up Air Up, for example, utilises a proprietary bottle design to flavour water through smell alone. It uses specially-designed scent pods, and aims to reduce the amount of sugar and other additives which are usually consumed in traditional soft drinks.

Miyashita and Kirin will now work together to further fine-tune the device, and hope to commercialise the chopsticks as early as next year.