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added pic of ropy beer from Stuart Grant
==="Ropy" or "Sick" Beer===
[[File:EPSRopy example.gifjpg|thumb|300|Exopolysaccharide pathway Example of ropy beer brewed with The Yeast Bay Melange and dregs from Boon Mariage Parfait 2010. Photo is courtesy of Stuart Grant <ref name="ESP">[httphttps://www.sciencedirectfacebook.com/sciencegroups/articleMilkTheFunk/piipermalink/S0740002004000668 Glucose fermentation kinetics and exopolysaccharide production by ropy Pediococcus damnosus IOEB88011148859311808948/ Conversation with Stuart Grant on MTF. Emilie Walling, Marguerite Dols-Lafargue, Aline Lonvaud-Funel. Food Microbiology Volume 22, Issue 1, January 2005, Pages 71–7809/16/2015.]</ref>]]
Some strains of ''P. damnosus'' can cause a beer (or wine) to go "ropy". Reportedly, ropiness in beer that also has ''Brettanomyces'' (which is traditionally credited with breaking down the ropiness after a period of rest) usually lasts anywhere from 1 week to 3 months, although fewer reports claim that it has lasted as long as 7 months (see reference for different experiences of brewers) <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1132030550158491/ Poll on Milk The Funk regarding how long ropy beer has been observed. 08/20/2015.]</ref>. This "ropiness" is actually caused by production of exopolysaccharides (EPS) in the form of β-glucans (beta glucans). A small amount of β-glucan is adequate enough to affect the visible viscosity of beer or wine. The gene known as Dps has been identified with the production of β-glucan/EPS. Not all strains of ''P. damnosus'' express the gene, and only ones that do will cause a beer to go ropy. ''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 <ref name="ESP"></ref>.
It has been observed that ''Lactobacillus'' species can produce EPS (''Lactococcus lactis'', ''Lactobacillus delbrueckii'', ''Lactobacillus casei'', and ''Lactobacillus helveticus'') <ref name="ESP"></ref>.
[[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>]]
===Other Metabolites===