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added tannase information in "Sugar Utilization and Primary/Secondary Metabolites"
A small number of strains of ''Lactobacillus'' can also break down polysaccharides and starches. They are referred to as "amylolytic LAB". They generally belong to the species ''Lb. manihotivorans'', ''L. fermentum'', ''L. amylovorus'', ''L. amylophilus'', ''L. plantarum'' or ''L. amylolyticus''. This seems to be associated with a gene called "amyA", which encodes for extracellular alpha-amylase activity, as well as alpha-glucosidase, neopullulanase, amylopectin phosphorylase, and maltose phosphorylase. This activity is limited by high amounts of glucose, maltose, or sucrose <ref name="peyer_review"></ref>.
Many strains of ''Lactobacillus'' and other lactic acid bacteria can produce tannase, which is an enzyme that breaks down a certain class of tannins called "hydrolizable tannins" (for example, tannic acid). The enzymatic breakdown of tannins provides a food source for the ''Lactobacillus''. In the cited study, a strain of ''L. plantarum'' was selected out of 47 other tannase producing LAB as being the highest producer of this enzyme. Although the optimum pH for tannase is 5-8, it is also at least 50% active at a pH of 3-7 and a temperature of 15-30°C. Tannase has been produced as a product for removing haze in food products such as iced tea, wine, and beer <ref>[http://www.asbcnet.org/publications/journal/vol/2016/Pages/ASBCJ-2016-4298-01.aspx Purification and Characteristics of Tannase Produced by Lactic Acid Bacteria, Lactobacillus plantarum H78. Mari Matsuda, Yayoi Hirose, and Makoto Kanauchi. 2016.]</ref><ref>[http://www.beveragedaily.com/R-D/New-enzyme-aims-to-take-the-haze-out-of-iced-tea "http://www.beveragedaily.com/R-D/New-enzyme-aims-to-take-the-haze-out-of-iced-tea". Beveragedaily.com. Guy Montague-James. 04/04/2011. Retrieved 011/09/2016.]</ref>. Some ''Lactobacillus'' strains could therefore have a positive effect on beer clarity by breaking down haze forming tannins.
Lactic acid is the primary metabolite for ''Lactobacillus'', as well as CO2 and ethanol/acetate (acetic acid) in heterofermentative species. Acid production is at it's highest during the exponential growth phase, but continues into the stationary and decline phases. Typically just under 50% of the lactic acid produced is L-lactic acid (more nutritionally relevant) while the slight majority is D-lactic acid <ref name="Peyer"></ref>. The amount of lactic and acetic acids produced varies from species to species. For example, the referenced study showed that ''L. plantarum'' produces more than twice the amount of lactic acid than ''L. brevis'', and ''L. reuteri'' produced slightly more lactic acid than ''L. brevis''. ''L. reuteri'' produced around twice as much acetic acid than ''L. brevis'', and ''L. plantarum'' produced very little acetic acid. The small amount of acetic acid produced by ''L. plantarum'' in this study was explained by oxygen exposure during sampling, while the obligate heterofermentative species (''L. reuteri'' and ''L. brevis'') produced acetic acid as a direct result of their heterolactic fermentation <ref name="Peyer"></ref>.