Miki (Sacred Wine or Sake) (神酒)

Miki (also referred to as 'shinshu') is alcohol (generally Japanese sake) offered to Shinto deities. It is an essential part of food and alcohol offerings to the deities.

Summary
The term 'miki' is an eulogistic name for sake, formed by adding the honorific prefix 'mi' to 'ki,' meaning sake. It is usually called 'omiki,' the 'o' being a further honorific prefix.
In some ancient documents, miki is referred to as 'miwa.'
Omiwa-jinja Shrine (Miwa Myojin), which contains the same sound, is worshiped as a deity of sake brewing. There is a word 'kushi' seen in "Kojiki" (The Records of Ancient Matters), and a word 'ugusu' in Okinawa Prefecture. These are related to the word 'kushi' (strange), and are derived from the fact that the effects of alcohol were believed to be a 'kizui' (auspicious omen).

In rites and festivals, participants on the enshrining side also usually receive miki. This is based on the concept of eating and drinking the same food and drink as offered to the deity, as well as the belief that getting drunk to achieve an extraordinary state deepens exchanges with the deity.

Types and brewing methods
There are several types, including shiroki (white sake), kuroki (black sake), sumisake (refined sake), nigorizake (unrefined sake), and there are also various brewing methods. The 'ki' of shiroki and kuroki is an old term for sake, and can be written with the characters for alcohol or for precious. Kuroki is also referred to as kuromiki. According to the "Engishiki" (an ancient book for codes and procedures on national rites and prayers), shiroki was sake brewed from rice harvested from shinden (fields affiliated with a shrine) and filtered as it was, while kuroki was darkened by adding the ash of burned grass roots to shiroki. Probably because it was known that sesame enhances the liver's functioning, reishu (sweet half sake) darkened with black sesame powder was used to cure hangovers later in the Muromachi period.

Nowadays, the combination of sumisake and doburoku (unrefined sake) is often replaced by the combination of shiroki and kuroki. Miki used to be homebrewed by a shrine or shrine parishioner but now, due to regulation by the Liquor Tax Act, some shrines like Ise Jingu Shrine receive a license to brew sumisake, or a license to brew doburoku from the tax office.

Others
The purpose of brewing miki is explained on the "doburuku" page. According to one theory, the Edo period custom of offering shirozake (sake) at Doll's Festival derived from the custom of offering shiroki.