Description

Lactic acid bacteria (LAB) are a heterogeneous group of species, which synthesize lactic acid as the major product of sugar fermentations. LAB are an industrially important group of microorganisms used throughout the world for a large variety of food fermentations, such as those of dairy, wine, bread and vegetables.

The European Food Safety Agency (EFSA) has recently introduced a system for a premarket safety assessment of selected taxonomic groups of microorganisms leading to a ‘Qualified Presumption of Safety’ (QPS), the European equivalent of the Generally Recognized As Safe (GRAS) status. Several species of food associated LAB have obtained a QPS status. The adaptability of LAB to fermentation processes, their biosynthetic capacity and metabolic versatility, are some of the principal features that facilitate the application of LAB as microbial starters for producing, releasing and/or increasing specific beneficial compounds in fermented food. In addition, LAB produce compounds related to the food safety just contributing to prevent the growth of pathogens (i. e. antimicrobial peptides) or generating compounds which can cause serious health problems in humans (i. e. biogenic amines). Therefore, characterization and usage of new bacteriocins for food preservation and the detection, understanding and control of the biogenic amine production by LAB are subject of current studies in the field.

LAB are also natural members of the human gastrointestinal microbiota and several strains are considered beneficial to the host and have been selected for probiotic applications.

Likewise, there are a number of metabolites produced by these organisms, such as vitamins as well as certain polysaccharides (prebiotics) whose functions, among others, is to enhance the development of a microbiota that is beneficial to the human gastrointestinal tract, as well as possibly possessing an immunomodulating effect. These aspects constitute an important field of research that could lead to the production of fermented functional foods (and beverages) which benefit human health.