Changes

'''Butyric Acid''' (chemical name '''butyrate''' <ref>[https://en.wikipedia.org/wiki/Butyrate Butyrate. Wikipedia. Retrieved 6/20/2015.]</ref>) is a carboxylic acid that is produced by anaerobic bacteria such as ''Clostridium butyricum'', ''C. kluyveri'', and ''Megasphaera spp'' <ref name="wikipedia">[http://en.wikipedia.org/wiki/Butyric_acid#Production Wikipedia description of Butyric Acid production]</ref> during glucose fermentation, and is generally considered an off flavor in sour beer. If not done right, [[Sour Mashing]] can be a big producer of butyric acid. Butyric acid is produced by anaerobic bacteria. The aroma and flavor is often described as a vomit, bile, or rancid cheese. It is also present in the human gut, and is the cause of the aroma of vomit <ref name="wikipedia"></ref>. This is not to be confused with [[Isovaleric Acid]] which has a more "feety" aroma and flavor. [[Brettanomyces]] can convert butyric acid into [[Ethyl Butyrate]] at low levels, which has a pineapple, tropical fruit aroma and flavor <ref>[http://www.brettanomycesproject.com/dissertation/pure-culture-fermentation/pure-culture-fermentation-discussion/ Chad Yakobson's Brettanomyces Dissertation]</ref>, however if butyric acid levels are high enough for sensory detection then ''Brettanomyces'' will probably not convert enough of it to bring it down to below threshold levels <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1213199972041548/ Conversation with Brett Smith on MTF. 01/13/2016.]</ref>. Butyric acid has shown to have some health benefits in medical research <ref>[http://jmm.sgmjournals.org/content/59/2/141.full Van Immerseel F, Ducatelle R, De Vos M, Boon N, Van De Wiele T, Verbeke K, Rutgeerts P, Sas B, Louis P, Flint HJ. Butyric acid-producing anaerobic bacteria as a novel probiotic treatment approach for inflammatory bowel disease. J Med Microbiol 2010;59:141–3.]</ref><ref>[http://iai.asm.org/content/8/1/30.full.pdf Effect of Colon Flora and Short-Chain Fatty Acids on Growth In Vitro of Pseudomonas aeruginosa and Enterobacteriaceae. MATTHEW E. LEVISON. 1973.]</ref>.