Pure brown rice vinegar is a type of Japanese vinegar that is made from brown rice and water, and is not diluted with white vinegar as is often the case with other types of rice vinegar. pure brown rice vinegar has a dark brown colour and a slightly sweet, aromatic flavour. It is often used in Japanese cuisine to add flavour and aroma to dishes, such as marinades, sauces, soups and dressings. Pure brown rice vinegar can also be used as a condiment to season vegetables, noodles and rice.