Mirin(味醂or みりん?) is an essential condiment used in Japanese cuisine. It is a kind of rice wine similar to sake, but with a lower alcohol content and higher sugar content. The sugar content is a complex carbohydrate formed naturally via the fermentation process; it is not refined sugar. 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 well as 1.5% salt 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 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 (煮切り味醂) (literally: thoroughly boiled mirin).
A bottle of commercially produced Japanese mirin
Mirin is used to add a bright touch to grilled (broiled) fish or to erase the fishy smell. A small amount is often used instead of sugar and soy sauce. It should not be used in excess, however, as its flavor is quite strong. It is sometimes used to accompany sushi. Mirin is used in teriyaki sauce.
November 30 has been designated the Day of hon-mirin by the mirin industry because in Japanese wordplay the date words sound like '11' (いい, good) and '30' (みりん, mirin).