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→Effects of Mixed Cultures on Growth
Brian Martyniak showed that ''Brettanomyces'' growth can be inhibited by the concurrent growth of ''S. cerevisiae'' under anaerobic conditions. In aerobic conditions, oxygen appears to help ''Brettanomyces'' out-compete ''S. cerevisiae'' when ''S. cerevisiae'' is present in small quantities. The presence of lactic acid bacteria does not greatly effect ''Brettanomyces'' growth <ref name="Hubbe" /><ref name="martyniak">[https://www.facebook.com/groups/MilkTheFunk/permalink/1362220513806159/ MTF post by Brian Martyniak on ''Brettanomyces'' growth in competition with ''Saccharomyces'' under aerobic and anaerobic conditions. 07/29/2016.]</ref>. Hübbe showed a similar result by showing that both ''B. bruxellensis'' and ''B. anomalus'' grew essentially the same amount by themselves or with ''Lactobacillus'', but growth for both ''Brettanomyces'' species was greatly inhibited when co-fermented with ''S. cerevisiae''. Therefore, when making starters for mixed cultures of ''Brettanomyces'' and ''Saccharomyces'', the brewer might be able to favor ''Saccharomyces'' by limiting oxygen, or favor ''Brettanomyces'' by introducing oxygen during growth. Data from Thomas Hübbe and Mark Trent support that the initial pitching rate doesn't have a great effect on the final cell count in pure ''Brettanomyces'' starters or beer, indicating that ''Brettanomyces'' is fairly forgiving in regards to small initial cell counts <ref name="Hubbe" /><ref>[[Brettanomyces_Propagation_Experiment|MTF ''Brettanomyces'' Propagation Experiment]]</ref>.
At last one report exists of a hybridization events in a mixed/spontaneous beer fermentation. These hybridization events were the result of ''S. cerevisiae'' and ''S. uvarum'' hybridizations. The potential parent strains were screened for sporulation and were found to be able to sporulate (the hybrids were not able to sporulate). This same group reported changes to the STA1+ genes that differed from the pitched diastatic strains . This demonstrates that the general concept of "uncontrolled genetic drift" is at least possible in mixed cultures <ref>[https://www.pnas.org/doi/abs/10.1073/pnas.1105430108 Microbe domestication and the identification of the wild genetic stock of lager-brewing yeast. Diego Libkind, Chris Todd Hittinger, Elisabete Valério, Carla Gonçalves, Jim Dover, Mark Johnston, Paula Gonçalves, and José Paulo Sampaio. DOI: https://doi.org/10.1073/pnas.1105430108. 2011.] See also [https://www.facebook.com/groups/MilkTheFunk/posts/7415625611798922/?comment_id=7427190037309146 this MTF thread]</ref>.
* See also [[Mixed Fermentation]].