The network of the bioindustry of Hokkaido, and cooperation and market expansion with partners.

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Material introduction of functional foods

One of Hokkaido's representative vegetables is the onion. Onion farming began in Sapporo, and presently the most commonly produced onion is the yellow globe Danvers. Functional research on onions in Japan became full-blown in the 1980's, and in 1989 the first onion supplement in Japan was created. The main component is different between the edible part and the outer skins; the edible part containing sulfuric compounds, the outer skin contains high concentrations of quercetin, a type of flavonoid. In Hokkaido, ministry, academia and industry is working together to develop a functional ingredient containing DPTS, a secondary metabolite produced when possessing onions under certain conditions. This research is drawing much attention. Due to further breed improvement, a new type of onion containing high amounts of quercetin have been born. There is high hopes concerning the use of such onions in supplements.
Onions are perennials and a member of the Alliums family, which like green onions, Chinese chives and garlic have a strong aroma. They originate in Iran, Afghanistan, Pakistan and other central Asian areas, but a wild variety has not been discovered. Cultivation history goes back to 4000 BC where in Egypt they were cultivated for edible purposes. Afterward, onions spread to the Mediterranean coasts of Europe, then on to America. In Europe and India where onions have been eaten for a long time, they were used in folk medicine to treat fever, water retention and gastric inflammation. England, France and India especially devoted time in researching and developing onions and have proved their effectiveness in treating diabetes, hyperlipidemia, and improving circulation.
In Japan, cultivation of onions was implemented in Sapporo, and the Sapporo School of Agriculture (presently Hokkaido University) was first to begin full-fledged cultivation. Hokkaido dominates around 50% of the onion production in Japan, of which a fourth is grown in Kitami City. The breed is different with color, and can be roughly divided into white, yellow and red onions. The white onions are known as new onions which come into distribution in spring, but the yellow onions are most commonly grown in Japan.
In Japan, due to the establishment of a project related on functional research of onions by the Ministry of Agriculture, Forestry and Fisheries, data accumulation has progressed resulting in development of the first onion supplement in 1989. With a background of research on vegetable foods and designer foods effective for fighting cancer, provided by the American Cancer Research Center and argument by Fine Chemicals, the supplement created such hype that supplies ran short.
Main components in onions can be divided into two major categories; sulfuric compounds and quercetin, a type of flavonoid. the sulfuric compounds are found in the edible part of the onion, while the quercetin is found in both the edible part and the skin. The sulfuric compounds are what give onions their signature strong aroma. These components are propenyl cysteine sulfoxide, Cycloalliin,allyl propyl disulfide and over a hundred other types, and are effective in lowering blood pressure, lowering blood sugars, improving blood circulation, platelet aggregation action according to research reports. Sulfuric compounds are also found in garlic, but oinons contain a richer variety than garlic. Functional ingredients include onion powder, paste, spray-dried onions, extract and vinegar which are used in pills, capsules, soup, tea, candy and gelatin.

dipropyl trisulfide DPTS

It is known that when onions are processed under certain conditions a secondary product called DPTS(dipropyl trisulfide) is increased. This is made possible by using the onions' defense mechanism to work on the enzymes to produce a defensive element that is good for the human body. After cutting the onions, trisulfides and sepaens are created through enzyme and thermal chemical reaction. In functional research using DPTS, it proven to help improve memory deficit in learning, and help to control acidification of the hippocampus, the part of the brain responsible for memory. Studies also show that it is effective for improving blood fluidity, blood components, sensitivity to cold, hepatic function and more.


Of all the imported fresh produce, onions are the highest in amount, and conflict among the growing areas is increasing. For this reason, cross-breeding is used to create new onions with higher concentrations of quercetin, to attempt differentiation from other onions. In Kuriyama, Hokkaido, government, industry and academia together established the [Kuriyama Onion Project], to promote a new onion called [Sara Sara Red]. This onion was created by gathering over 300 types of onions from around the world and cross-bred to develop an onion containing the highest amounts of quercetin and sulfuric compounds. Compared to ordinary onions, it contained between 1.5 - 3 times the amount of quercetin, the highest amount found in onions in Japan. Just as it is named, the onion is red and contains a type of polyphenol called anthocyanin.
Onions have a greater amount of quercetin than other vegetables and fruit, and have a higher absorbency level. Functional research using quercetin from onions revealed hypo-allergenic effects, protection against UV rays, effects to lower blood sugars, antioxidant actions, prevention against fat absorption, and prevention of carcinogenesis.

List of cooperating industries for this coverage.

The introduced content on Hokkaido's functional food ingredients was brought to you in cooperation with the following industries and products.
Industries Major Products
Hokkaido Bio-Industry Corporation BRC Onions (DPTS contained onion products)
Plant Breeding Research Co., Ltd. Kuriyama Health Onions Sarasara Red