The lactic acid produced by a Gram-positive bacterium called Lactococcus lactis is needed in cheese formation, as well as the production of fresh vegetables, and other fermented foodstuffs.
Other uses that have been reported for this bacterium include the production of pickled vegetables, beer or wine, some breads, and other fermented foodstuffs, such as soymilk kefir, buttermilk, and others. 
