Photo/Illutration Kobayashi Pharmaceutical Co.’s "Benikoji coleste-help" supplement (Provided by Kobayashi Pharmaceutical Co.)

While benikoji has been widely used in food and other products, recent deaths and health problems associated with the malted rice ingredient have thrust it into the spotlight as a potential health hazard. 

Kobayashi Pharmaceutical Co.’s “Benikoji coleste-help” dietary supplement has been reported to have caused a series of health concerns, prompting recalls of the company's products.  

There have been reports of health problems overseas in the past that are suspected to have been caused by consumption of supplements made from benikoji.

HOW IS BENIKOJI MADE?

Benikoji is made by mixing benikoji bacteria with steamed rice and fermenting the mixture. The fermentation produces a red pigment.

Traditionally, benikoji has been used to make Chinese sake and Okinawan fermented tofu.

In recent years, it has been used as an ingredient in health foods because it is believed to lower LDL cholesterol, also known as bad cholesterol, in the blood.

According to the Food Safety Commission, there have been reports of health problems in Europe suspected to have been caused by consumption of supplements derived from rice fermented with benikoji.

In 2014, the European Commission, which is responsible for the administration of the European Union, set standards and regulated supplements for citrinin, a toxic chemical produced by the benikoji bacteria.

In 2019, the standard was further lowered and regulations were tightened.

In 2014, Switzerland banned the sale of food products containing benikoji, and France urged people to consult their doctors before using such supplements.

However, Kobayashi Pharmaceutical said it used a strain of bacteria that does not produce citrinin, and the chemical was not detected in the analysis of all lots of raw materials conducted in February this year.

In 2016, the company took over the production and sales business related to benikoji from Gunze Limited, a textile products company based in Osaka.

Kobayashi Pharmaceutical then developed a mass-cultivation process using the traditional solid-state fermentation method. Under the method, benikoji bacteria are planted on rice, cultivated, heated, crushed and stored.

The ingredients are then mixed to a certain consistency, reheated and packaged to complete the benikoji raw materials. The raw materials are manufactured at the company’s own plant, and the supplements are made by supplying the materials to partner plants.

The company launched “Benikoji coleste-help” in 2021. This was the first functional food labeled with ingredients derived from benikoji.

The manufactured benikoji raw materials are sold to companies for use in coloring and flavoring food and food products, in addition to use in supplements.

According to the company, the ingredients used for food products are different from those utilized for supplements, and no unknown ingredients have been found that are believed to pose a health hazard.

Among the products derived from benikoji bacteria is the food additive called benikoji dye, which is used in a wide range of foods.

However, this is a dye extracted from the culture solution of benikoji bacteria and differs from the benikoji raw materials that are causing health problems.

The official standard for food additives based on the Food Sanitation Law specifies the upper limit of impurities and other standard criteria.

(This article was written by Mika Omura and Mihoko Terada.)