Rice vinegar is made from fermented rice and is popular in China, Japan, Korea and Vietnam.
There is often confusion between rice vinegar and rice wine. Rice vinegar is made much as rice wine is - by fermenting rice and converting it to alcohol - however, bacteria is then added to the fermentation process to turn the alcohol into an acid.
Several varieties of rice vinegar exist but can be broken down into three basic types: white, black and red.
"Rice vinegar." Wikipedia, The Free Encyclopedia. 23 Oct 2009, 11:54 UTC. 24 Dec 2009.