Mirin is an essential condiment used in Japanese cuisine. It is a type of rice wine similar to sake, but with a lower alcohol content and higher sugar content. The sugar content is a complex carbohydrate that forms naturally during the fermentation process; no sugars are added. The alcohol content is further lowered when the liquid is heated.

There are three general types of mirin. The first is hon mirin (literally: true mirin), which contains approximately 14% alcohol and is produced by a forty- to sixty-day mashing (saccharification) process. The second is shio mirin, which contains alcohol as low as 1.5% to avoid alcohol tax. The third is shin mirin (literally: new mirin), or mirin-fu chomiryo (literally: mirin-like seasoning), which contains less than 1% alcohol yet retains the same flavor.

In the Edo period, mirin was consumed as Amazake. Otoso, traditionally consumed on Shōgatsu, can be made by soaking a spice mixture in mirin. In the Kansai style of cooking, mirin is briefly boiled before using, to allow some of the alcohol to evaporate, while in the Kantō regional style, the mirin is used untreated. Kansai-style boiled mirin is called nikiri mirin (literally: thoroughly boiled mirin).

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