heterolaktic

Heterolactic is a term used to describe a type of fermentation, specifically a metabolic pathway that produces lactic acid along with other products. This is in contrast to homolactic fermentation, which exclusively yields lactic acid. In heterolactic fermentation, microorganisms break down carbohydrates, such as sugars, to produce not only lactic acid but also ethanol, acetic acid, carbon dioxide, and/or other organic acids.

The specific products and their ratios can vary depending on the microorganisms involved and the environmental conditions, such as temperature and pH. Common examples of bacteria that exhibit heterolactic fermentation include species of Leuconostoc and some Lactococcus and Lactobacillus strains. These bacteria often play roles in the spoilage of food or in the production of certain fermented foods where a complex flavor profile is desired.

Heterolactic fermentation is a significant metabolic process in various microbial communities and industrial applications. For instance, in the dairy industry, some strains of lactic acid bacteria can undergo heterolactic fermentation, contributing to the flavor and texture of products like yogurt and certain cheeses. Understanding heterolactic fermentation is important for controlling food spoilage and for optimizing the production of fermented goods. The biochemical pathways involved are distinct from homolactic fermentation and are characterized by the presence of enzymes like phosphoketolase, which shunts a portion of the glycolytic pathway towards the production of additional end products beyond lactate.