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Rogers et al. found an easy solution to carbonating low pH, high ABV beers by first acclimating the yeast to the sour beer. Growing the yeast in YPD plus lactic acid plus ethanol was not enough to acclimate the yeast and reliably carbonate a highly acidic, alcoholic (8% ABV) beer. However, by growing the yeast first in a blend of YPD that was diluted with the sour beer itself in a 1:1 ratio, they found that both CBC-1 and WLP715 were then able to carbonate the sour beer (WLP001, WY1056, WY2007, and WLP300 were not given this treatment). This was explained as exploiting the microbes' resilience and ability to adapt to many environmental conditions by "pre-adapting" the yeast to the harsh conditions of the sour beer <ref name="rogers2016"></ref>. It has been speculated that brewers without access to YPD might be able to achieve similar results by growing the conditioning yeast in sour beer diluted with DME wort and yeast nutrients (Fermaid K and DAP, for example) <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1259063934121818/?comment_id=1262875587073986&reply_comment_id=1263142900380588&comment_tracking=%7B%22tn%22%3A%22R9%22%7D Conversation with Richard Preiss and Tamir Danon on acclimating yeast to sour beer for conditioning on MTF. 03/24/2016.]</ref>.
A second study showed that a strain of ''S. cerevisiae'' was able to adapt and grow in a lab setting to increasing concentrations of lactic acid. After multiple generations and by slowly increasing the amount of lactic acid per generation, the researchers got the pH of the growth media (either raffinose or glucose plus lactic acid) all the way down to pH 2.8. At this low pH, the yeast began to use lactic acid as a food source. This might explain some anecdotal experiences by brewers who have seen the pH of kettle sour beers rise (more evidence is needed to confirm this hypothesis). The researchers found that the gene called ''ACE2'' is likely to be associated with the ability to adapt to low pH conditions. It is also a gene that controls the expression level of other genes, and is also responsible for forming "snowflake-like" structures (multicellular clumps of genetically identical cells that stick together after budding <ref>[https://www.quantamagazine.org/20151103-snowflake-yeast-multicellularity/ "Life’s Secrets Sought in a Snowflake". Emily Singer. Quantum Magazine. 11/03/2015. Retrieved 12/27/2016.]</ref>). The yeast strain began to form these "snowflake-like" clumps after being adapted to the low pH environment. Further work should be done to determine which strains of ''S. cerevisiae'' might be more easily adapted to low pH environments, or if possibly all strains of ''S. cerevisiae'' could be adapted to low pH environments over time <ref>[http://www.sciencedirect.com/science/article/pii/S1096717616301756 Evolutionary engineering reveals divergent paths when yeast is adapted to different acidic environments. Eugene Fletcher, Amir Feizi, Markus M.M. Bisschops, Björn M. Hallström, Sakda Khoomrung, Verena Siewers, Jens Nielsen. 2016.]</ref><ref>[http://www.nature.com/articles/ncomms7102 Origins of multicellular evolvability in snowflake yeast. William C. Ratcliff, Johnathon D. Fankhauser, David W. Rogers, Duncan Greig & Michael Travisano. 2015.]</ref><ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1530874020274140/ Conversation on MTF with Richard Preiss about yeast adaption to low pH environments. 12/27/2016.]</ref>.
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