Japanese smoked radish is a traditional meal prepared since the period Muromachi (1336-1573) in the Akita region, north of Japan. Known locally under the name of Iburigakko, it is made by smoking first white Japanese radish (Daikon) before fermenting.
The production begins at the beginning of the winter. However, Akita, prefecture where it is traditionally produced, is one of Japan's most snowy regions, making it difficult to dry out of agricultural products. In the past, households suspended the radish above the "irori", a traditional interior household, where they were slightly smoked by the ascending smoke of firewood. This method dehydrates the radish while giving it a characteristic aroma.
Nowadays, the manufacturing process always begins in winter, in December, at the end of the agricultural season, by smoking radish for three days, using cherry and oak wood.
The radishes are suspended above the fire, recreating the tradition of the Muromachi era, which consisted of smoking above the Irror (home-domestic home present in Japanese minka dwellings).
The radish of a pure white then gradually take a deep smoked hue.
After 3 days, the doors of the smoker open.
The radish, slightly dried by the smoke, are golden and firm.
Their aroma is rich and mellow, impregnated with a smell of smoke.
After smoking, they are rinsed once in the water.
Then comes the second step: the marinalization.
The radishes are plunged, arranged in layers, in a fermentation bed consisting of sound of rice and other traditional ingredients, salt, sugar and vinegar, where they suffer a slow lactic fermentation.
Hermetically closed, bins promote the fermentation of vegetable lactic bacteria.
The fermentation of Japanese smoked radish has similarities with the malolactic fermentation used in the vinification processes, with a low temperature fermentation that lasts about two months.
In February, the marinade is over and the Iburigakko is ready, reduced to about a quarter of its initial weight, which gives it its characteristic crunch.
The first step in the Iburigakko manufacturing process is to cut each piece in half.
The iburigakko can then be kept as is or to be sliced or cut into small pieces.
An original storage liquid is then added and the product is packed under vacuum, and then subjected to autoclave treatment to ensure a long storage.
Originally, the Iburigakko was appreciated as a winter conservation food, offering both flavor and nutrient during the rigorous season.
In recent years, Iburigakko has experienced renewed popularity. It is now widely appreciated in cheese support and also raises interest as a tasty ingredient in sushi and onigiri. Today, it is proposed in a wide variety of products by the main channels of Japanese proximity stores.
