Azuki beans are considered one of the oldest foods consumed in Japan as they have appeared in Japanese mythology as well as excavated from an over 3000-year old ruins. In Japanese cuisine, azuki beans are widely accepted as a food of celebration when cooked together with glutinous rice as sekihan. This likely came from the Chinese belief, which spread to Japan, that the red color of azuki beans can act as a charm against evil.
Red bean paste made by cooking rehydrated azuki beans in sugar until reduced is used in a wide range of Japanese sweets such as ohagi and daifuku. The sweet red bean paste can also be strained for making red bean porridge or red bean jelly dessert.
There is well established popularity throughout Japan for Tokachi-grown azuki beans, as the Tokachi area, which includes Otofuke Town, Memuro Town, and Obihiro City, is one of the major growing regions.
■Map / Main producing municipalities
Otofuke Town, Memuro Town, Obihiro City, Makubetsu Town, Shihoro Town, Sarabetsu Town, Shimizu Town, Toyokoro Town, Honbetsu Town, Ikeda Town
Even though azuki beans do not grow well in a climate with low temperatures or high humidity, as the crop rearing period is short, it is possible to grow azuki beans in a cold climate such as Hokkaido’s. Typically, azuki beans have been considered an unstable crop as the yield is subject to weather conditions including damage in cold weather. However, the azuki beans that grow steadily while braving the cold weather of Hokkaido are known for their delicious taste.
The secret to their deliciousness lies in the increased amount of carbohydrates caused by the temperature fluctuation. Areas such as Tokachi that have a great temperature fluctuation between day and night grow azuki beans with a sweet taste and tender texture when cooked because of the large amount of carbohydrates contained in the beans.
On a related note, the Ise Grand Shrine in Mie Prefecture that attracts many visitors from Japan and abroad every year has been known for the ankoro mochi sweet cake sold nearby for many years. Currently, their sweet red bean paste is made using Hokkaido-grown azuki, garnering an increased popularity among visitors.
In Hokkaido, the seeding period of azuki beans is from mid May to early June. However, just prior to that, seeds are disinfected in order to prevent disease and pests. The flowering season begins in late July for roughly one month, while the beans are harvested around September and October.