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==Microbial Succession During Fermentation==
(In Progress)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 name="Bokulic et al., 2012" /> <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" />. This as been illustrated well by Raj Apte <ref>[http://www2.parc.com/emdl/members/apte/slides_nchf.pdf/ Raj Apte Concepts of sour Beer, 2004]</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-dominated stage <ref name="Van Oevelen et al., 1977" />. 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?)
==''Spontaneous Fermentation'' versus ''Mixed Fermentation''==
==External Resources==
A list of external internet resources and articles for ''spontaneous fermentation''.
* [[Scientific Publications]]
* [http://www.thebrewingnetwork.com/membersarchive/sourhour2015_05_wildfriendship.mp3 The Sour Hour Episode 11 with Rob Tod and Jason Perkins from Allagash, Jean Van Roy from Cantillon, and of course, Vinnie Cilurzo] ([https://itunes.apple.com/us/podcast/the-sour-hour/id920652546?mt=2# iTunes]).
* [http://thebrewingnetwork.com/shows/751 Jean Van Roy on The Brewing Network's Sunday Session]