Kirin Holdings and the Miyashita Laboratory at Meiji University have developed the “world’s first” chopsticks that can make food seem 1.5 times saltier with the use of a weak electric current. 

Researchers believe the innovation could help enhance the taste of low-sodium foods, giving consumers who need to maintain a low-salt diet low in salt more eating satisfaction.

The study confirmed that the salty taste intensity of a 30% reduced-salt food was the same as that of an ordinary food sample when electric stimulation was applied. 

The findings suggest as much as 30% of salt can therefore be reduced with the aid of the electrified device. 

Adjusting ions 
Since 2019, Kirin Holdings and Miyashita Laboratory have been working on an electric taste sensation on everyday utensils such as chopsticks, spoons and tea bowls. 

The study confirmed that the salty taste intensity of a 30% reduced-salt food was the same as that of an ordinary food sample when electric stimulation was applied (Credit: Kirin).This process uses very weak electricity to adjust the function of ions such as sodium chloride (the basis of salty taste) and sodium glutamate (the basis of sweet taste) to change the perception of taste by making food seem to taste stronger or weaker.

The electrical stimulation waveform combined the effects of cathodal stimulation and anodal stimulation and showed an enhanced saltier taste compared to existing waveforms.

Researchers note that the waveform is not strong enough to have an effect on the human body. 

Putting it to the test
The proof of concept was verified in a recent clinical study conducted on 36 men and women aged 40 to 65 years old who follow or have followed a low-sodium diet. 

The group was tested using a chopstick-type device that delivers weak electrical stimulation to samples that imitate ordinary food (gel containing 0.80% salt) and samples that imitate reduced-salt food (gel containing 0.56% salt). 

In addition, in an experiment using reduced-sodium miso soup, the salty taste enhancement effect was /confirm/ied, and the participants commented they felt an improvement in richness, sweetness and overall tastiness.

The need to reduce salt
The latest innovation comes in response to the worldwide impetus to reduce salt. 

Sodium reduction has been in the spotlight, as front-of-pack labeling like the Nutri-Score and advocacy groups such as Action on Salt have raised increasing awareness of its dangers. 

The chopsticks using electrical waveforms are still in development (Credit: Kirin).Consumers are also leading the charge, with Innova Market Insights reporting that two in five global consumers said they had decreased their sodium/salt intake in the past 12 months in a 2021 survey.

The daily salt intake of Japanese adults is 10.9 g for men and 9.3 g for women, which is nearly double the amount the World Health Organization recommends at 5 g per adult. 

The Ministry of Health, Labor and Welfare in Japan suggests limiting salt intake to less than 8 g per day to prevent lifestyle-related diseases (less than 8 g per day for adult men and less than 7 g per day for adult women).

That means the current salt intake in the Japanese diet needs to be reduced by more than 20%, Kirin notes. But many consumers find low-sodium diets to be “bland,” and this has been a hurdle to maintaining a low-sodium diet.

Looking ahead
Kirin Holdings will continue to develop new services that support lifestyle disease prevention by increasing dietary satisfaction to make consumers’ diets tastier, more enjoyable and healthier. 

In the future, Kirin Holdings and the Miyashita Laboratory aim to use the results of this joint research to provide both mental satisfaction from a richer perceived taste along with health benefits derived from nutritional aspects for those who follow a low-sodium diet.

Salt increasingly in focus
A recent report by Ajinomoto flagged that the weight of salt reduction responsibility should be shouldered by industry rather than consumers. Innova Market Insights observes that low/no/reduced salt claims have increased in every major region of the globe, with Europe holding the most share of new products in this arena (Global, 2017 to 2021).

In the US, the Food and Drug Administration unveiled voluntary sodium reduction targets last October for a broad range of processed, packaged and prepared foods. 

Meanwhile, a recent study by the Canadian Institutes of Health Research found that lowering sodium intake in chronic heart failure patients could improve quality of life by reducing swelling, tiredness and coughing. However, it did not result in fewer emergency visits, hospitalizations or deaths in heart failure patients.