Acetic acid bacteria (AAB)  are a group of gram-negative or gram-variable obligate  aerobic bacteria, which can oxidize ethanol, sugar or  sugar alcohol to corresponding organic acids such as acetic acid,  gluconic acid and indole-3-acetic acid in  presence of oxygen. The denomination of AAB originates from their  abilities to produce acetic acid, which is the uppermost constituents in  vinegar. Current  researches show that besides producing the various organic acids, AAB can  also produce cellulose and sorbose, yield plant growth-promoters, synthesize surfactants, yellow pigments and brown pigments and eliminate formaldehyde. However,  AAB may destroy   beverages through depleting the products, forming a undesirable vinegary  off-flavors or influencing the growth of  dominant microorganisms, and some AAB strains are even pathogenic. Obviously, AAB are closely related to our daily life.