The Lactic Acid bacteria, although consisting of a number of diverse genera, are groupedas either Homofermenters or Heterofermentersbased on the end product of their fermentation.The Homofermenters produce lactic acid as themajor product of fermentation of glucose. TheHeterofermenters produce a number of products besides lactic acid, including carbon dioxide, acetic acid, and ethanol from the fermentation of glucose. The Homofermenters possessthe enzyme aldolase and are able to fermentglucose more directly to lactic acid than theHeterofermenters. The Heterofermenters use thealternate pentose monophosphate pathway, converting six carbon sugars (hexoses) to five carbon sugars (pentoses) by the enzyme phosphoketolase, producing in the process bothaldehyde and diacetyl—highly desirable aromatic and flavor-enhancing substances. TheHeterofermenters are often used in dairy industry because of these flavor-enhancing substances.2,22,27,28