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A lot of updates to Pedio. Still need to do diacetyl production.
[[File:Pedio.jpg|thumb|200px|right|Pediococcus - picture taken by Per Karlsson]]
'''Pediococcus''' (often referred to as ''Pedio'') are gram Gram-positive lactic acid bacteria (LAB) used in the production of Belgian style beers where additional acidity is desirable. They are native to plant material and fruits <ref name="ucdavis">[http://wineserver.ucdavis.edu/industry/enology/winemicro/winebacteria/pediococcus_damnosus.html Viticulture & Enology. UC Davis website. Pedioccous damnosus. Retreived 07/28/2015.]</ref>, and often found in gueuze spontaneously fermented beer as the primary source of lactic acid production (with ''P. damnosus'' being the only species identified in such beers) <ref>[http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0095384 The Microbial Diversity of Traditional Spontaneously Fermented Lambic Beer. Freek Spitaels, Anneleen D. Wieme, Maarten Janssens, Maarten Aerts, Heide-Marie Daniel, Anita Van Landschoot, Luc De Vuyst, Peter Vandamme. April 18, 2014.]</ref><ref>[[Scientific_Publications#Lambic_and_Spontaneous_Fermentation Multiple Scientific publications linked on MTF.]]</ref>. They are facultative anaerobes, meaning that they are capable of metabolism in both aerobic and other Belgian styles anaerobic environments. Strains found in beer are hop tolerant <ref>[http://www.biomedcentral.com/1471-2164/16/267 Comparative genome analysis of sour Pediococcus damnosus LMG 28219, a strain well-adapted to the beerenvironment. Isabel Snauwaert, Pieter Stragier, Luc De Vuyst and Peter Vandamme. April 2015.]</ref>. Due to their continued metabolism of longer chain polysaccharides, acid production will increase with storage time. ''Pediococcus'' species are generally more tolerant of antimicrobial hop acids and higher levels of acidity than ''[[Lactobacillus]]''. ''Pedio'' can form a [[pellicle]].
''Pediococcus'' may also cause “ropiness” (also called a "sick beer") due to the production of exopolysaccharides. "Ropy" or "sick" beer is more viscous and, in extreme circumstances, can form strands. Sickness effects mostly the mouthfeel and appearance of beer, and may have no influence on the flavor. ''Pediococcus'' species can also produce diacetyl with extended storage time. [[Brettanomyces]] can break down exopolysaccharides and diacetyl produced by ''Pediococcus'' and the two are often used together.
===Manufacturer Tips===
====[[Wyeast]] on 5733====
====[[White Labs]] on WLP661====
===Tips From MTF===
====The Rare Barrel====
==Metabolism==
===Lactic Acid Production===
[[File:Pedio sugars.JPG|thumb|300|Pedio fermentables <ref>Wine Microbiology. Practical Applications and Procedures. Kenneth C. Fugelsang, Charles G. Edwards.</ref>]]
About 90% of sugar metabolized by ''Pediococcus'' produces lactic acid. It does so by homolactic fermentation (same EMP pathway as [[Lactobacillus#Types_of_Metabolism ''Lactobacillus'' homolactic fermentation), although some species/strains can convert glycerol to lactic acid, acetic acid, acetoin, and CO2 under aerobic conditions (''P. damnosus'' is not in this category) <ref>[https://books.google.com/books?id=1b1CAgAAQBAJ&pg=RA2-PA1&lpg=RA2-PA1&dq=pediococcus+damnosus+homolactic&source=bl&ots=myI2alVB78&sig=cG-yWB4GuABQFEtqD2CAyKmU0TE&hl=en&sa=X&ved=0CEAQ6AEwBGoVChMI66C5593-xgIVCVKICh3Pcg7c#v=onepage&q=pediococcus%20damnosus%20homolactic&f=false Encyclopedia of Food Microbiology. Pediococcus. Carl A. Batt. Academic Press, Sep 28, 1999 .]</ref>. ''P. damnosus'' can ferment glucose, sucrose, and galactose. Some strains can ferment maltose and sucrose <ref name="ucdavis"></ref>.
===Growth and Environment===
''P. damnosus'' is sensitive to temperature and pH. It is unable to grow at a pH of 8 or higher or at 35°C. The optimal growth occurs at 22°C and 5.5 pH. ''P. damnosus'' is sensitive to environments that contain NaCl, and will not grow with concentrations of 4% NaCl <ref name="ucdavis"></ref>.
One study showed that by starting growth in a medium ([http://www.neogen.com/Acumedia/pdf/ProdInfo/7406_PI.pdf MRS media] that began with a pH of 6.7, and allowing the pH to drop to 4.14 naturally from fermentation, that better growth was observed. The addition of bacteriological peptone, MnSO4, and Tween 80 also increased activity <ref>[http://www.ncbi.nlm.nih.gov/pubmed/11851822 Nel HA, Bauer R, Vandamme EJ, Dicks LM. Growth optimization of Pediococcus damnosus NCFB 1832 and the influence of pH and nutrients on the production of pediocin PD-1. Department of Microbiology, University of Stellenbosch, Stellenbosch, South Africa. Dec 2001.]</ref>.
==See Also==