Many of these compounds inhibit microbial growth to increase the competition edge of the producing organism. Lactic acid bacteria are the most important of these natural antimicrobials.
Lactic acid bacteria represent a heterogeneous group of bacteria that includes several genera: Aerococcus, Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Streptococcus, Tetragenococcus, Vagococcus and Weissella.
Lactic acid bacteria have been used for centuries in fermentation, cheeses and sausages.
Some metabolites properties of lactic acid bacteria have been used traditionally to improve flavor development and ripening of fermented products and to prevent rapid spoilage of dairy foods and meat, as well as vegetables and silages. Foods traditionally fermented by lactic acid bacteria are preserved due to:
*The acidic pH resulting from the metabolism of sugars to lactic and acetic acids
*The increased concentration of undissociated acids and the concomitant decrease in available carbohydrates
*The production of antimicrobial metabolites such as H2O2 diacetyl, reuterin and bacteriocins
Many of these compounds kill or suppress food borne pathogens and spoilage microorganisms by acting on specific targets.
Lactic acid bacteria as natural antimicrobials
