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more on microbial succession.
Scientific research in Belgium and the US has shown a regular general pattern to the microbial succession of spontaneous fermentation beer. <ref name="Van Oevelen et al., 1977">[http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1977.tb03825.x/abstract/ Van Oevelen et al., 1977]</ref> <ref>[http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0035507/ Bokulich et al., 2014]</ref> <ref>[http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0095384#pone-0095384-g004/ Spitaels et al., 2014]</ref> <ref name="Spitaels et al., 2015">[http://www.sciencedirect.com/science/article/pii/S074000201500012X/ Spitaels et al. 2015]</ref>. The first stage, which lasts for approximately 1 month <ref name="Van Oevelen et al., 1977" /> <ref name="Martens et al., 1992">[http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.1992.tb01126.x/abstract/ Martens et al., 1992]</ref>, is dominated by ''enterobacteria''. Though ''enterobacteria'' contribute little in terms of gravity drop over the first month of fermentation, they may contribute aroma and flavor compounds and precursors during the initial stages of spontaneous fermentation <ref name="Martens et al., 1992" />. Acidifying the wort to pH = 4 before cooling and exposing to ambient microbes in a coolship can eliminate the ''enterobacteria'' phase of spontaneous fermentation <ref name="Spitaels et al., 2015" />.
The second stage of spontaneous fermentation is dominated by ''Saccharomyces sp.'' (predominantly ''S. cerevisiae'' and ''S. bayanus''). Most of the attenuation is accomplished during this stage, which lasts approximately 3-4 months <ref name="Van Oevelen et al., 1977" />. The ''Saccharomyces'' dominated stage of fermentation is followed by a bacterially-Sicknessdominated stage <ref name="Van Oevelen et al., 1977" /ropeyness >. The main bacteria present here are lactic acid bacteria, particularly ''Pediococcus damnosus''. Some ''Pediococcus'' strains are known to produce exopolysaccarides, resulting in "sick" or "ropey" - not all producers get this-- include (<ref name="Spontaneous Sour Hour" /> maybe ~1:10 min in?)
(To Do, include link to Raj Apte)