Supposedly, Heita forgot a vat of wine for 21 days and, remembering it at dusk, found it pleasantly sour.

Historical records for the present vinegar can be traced back 1400 years.

At that point, rice hull is added and mixed in once per day until the urn is full.

Salt is added and the urn is stored for up to 3 months during which it undergoes an aging process.

The vinegar is then leached and the soaking liquid from water-soaked, parched rice is added as a color and flavor enhancer.