Lactic Acid Bacteria in Table Olive Fermentation

Table olives are a fermented plant product.l The microbial flora involved in table olive fermentationare part of a complex ecosystem, which is influencedby several intrinsic and extrinsic factors related to brinecomposition. The microbial population initially presenton the olives is relevant.l Lactic acid bacteria (LAB) are part of the indigenousmicrobial flora of olives and determine, at least in part,the quality of the fermentation.l The indigenous LAB involved in table olive fermentationare predominantly lactobacilli. Species of the Leuconostoc,A polyphasic approach using culture-dependent andculture-independent methods (e.g. FISH) is required tounderstand the interactions which occur between indigenousmicrobial flora and the environment during thefermentation of olives.Streptococcus, Enterococcus, and Pediococcus genera arealso present in lower concentrations.l The main factors determining the growth of LAB populationduring spontaneous fermentation are salt concentrationand environmental pH.l Lactobacillus plantarum is the most common speciesfound during fermentation of both Spanish and blackolives because it is adaptable and very metabolicallyactive.l Lactobacillus pentosus, Lactobacillus brevis,Lactobacillus casei, Lactobacillus fermentum and someenterococci have also been found in olive brines.l LAB starter cultures may be added to accelerate andimprove the quality and consistency of fermentation.l The selection of LAB for starter cultures depends onvarious criteria including the ability to promote fermentationand improve the safety of table olives.l Bacteriocin production and probiotic properties areimportant features considered when LAB are selectedfor use as starter cultures.l The methods available for the detection and identificationof LAB species involved in table olive fermentationare very limited and generally culture-dependent.