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Pediococcus

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==="Ropy" or "Sick" Beer===
[[File:EPS.gif|thumb|300|Exopolysaccharide pathway <ref name="ESP">[http://www.sciencedirect.com/science/article/pii/S0740002004000668 Glucose fermentation kinetics and exopolysaccharide production by ropy Pediococcus damnosus IOEB8801. Emilie Walling, Marguerite Dols-Lafargue, Aline Lonvaud-Funel. Food Microbiology Volume 22, Issue 1, January 2005, Pages 71–78.]</ref>]]
Some strains of ''P. damnosus'' can cause a beer (or wine) to go "ropy". This "ropiness" is actually caused by β-glucan production, a type of exopolysaccharide (EPS). The gene known as Dps has been identified with the production of β-glucan/EPS. Pediococci that are ropy have been found to be more acid, alcohol, and SO2 tolerant than other Pediococci. The thickness of the ropiness is increased with the presence of malic acid. One study showed that the production of β-glucan coincided with the end of the growth phase of ''Pediococcus''. After 2 days of growth, β-glucan production increased as growth slowed. β-glucan production stopped when growth stopped. This would explain why beer containing ''Pedio'' often goes ropy in shortly after naturally carbonating in the bottle. This study found that other factors, such as alcohol levels. The study also found that the lack of agitation increased the β-glucan production. Higher initial pH encourages higher growth, so that also increased β-glucan production. Glocuse is needed for β-glucan production, while fructose is insufficient <ref name="ESP"></ref>.  ===Antibacterial Compounds===''P. damnosus'' has been found to create antibacterial compounds
==See Also==

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