Pediococcus

Pediococcus is a genus of Gram-positive lactic acid bacteria, placed within the family of Lactobacillaceae. They usually occur in pairs or tetrads, and are the only lactic acid cocci that divide along two planes of symmetry. They are purely homofermentative. Pediococcus bacteria are usually considered contaminants of beer and wine although their presence is sometimes desired in beer styles such as Lambic. Certain Pediococcus isolates produce diacetyl which gives a buttery or butterscotch aroma to some wines (such as Chardonnay) and a few styles of beer. Pediococcus species are often used in silage inoculants.