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''Brettanomyces'' has been identified on the skins of fruit (on the skins of cider apples for example) <ref name="smith_divol_2016"></ref><ref name="Schifferdecker"></ref>, as well as vectors (insects) <ref name="Steensels">[http://www.sciencedirect.com/science/article/pii/S0168160515001865 Brettanomyces yeasts — From spoilage organisms to valuable contributors to industrial fermentations. Jan Steensels, Luk Daenen, Philippe Malcorps, Guy Derdelinckx, Hubert Verachtert, Kevin J. Verstrepen. International Journal of Food Microbiology Volume 206, 3 August 2015, Pages 24–38.]</ref>. ''Brettanomyces'' is not considered to be airborne, however studies have found a very small amount of cells in the air at wineries where wine with ''Brettanomyces'' in it was being handled (most of the yeasts found in the air were ''Aureobasidium'' and ''Cryptococcus'', which aren't considered spoilage organisms in beer and wine). These set of studies also determined that very specific methodology was needed in order capture Brett from the air, and indicated that the yeast was "stressed". <ref>[http://www.sciencedirect.com/science/article/pii/S0956713513002284 Screening of yeast mycoflora in winery air samples and their risk of wine contamination. E. Ocón, P. Garijo, S. Sanz, C. Olarte, R. López, P. Santamaría, A.R. Gutiérrez. Food Control Volume 34, Issue 2, December 2013, Pages 261–267.]</ref>. While it is possible for ''Brettanomyces'' to be briefly carried by gusts of air, it only happens in the vicinity where the ''Brettanomyces'' beer or wine is being bottled (more so) or is actively fermenting (less so). Good cleaning and sanitation, and cold temperatures should be employed to keep ''Brettanomyces'' from infecting other equipment, and flying insects are a likely cause for cross contamination of ''Brettanomyces''.
''Brettanomyces'' is commonly isolated from the surface of wood structures within breweries, wineries, and cideries. These include structures such as wooden fermentation vessels, walls of the building, as well as the inside surface of wood barrels and actually buried within the wood of barrels. Although the role of ''Brettanomyces'' appears to be limited in distillation, it has been isolated during the fermentation process of tequila making. It has also been isolated from drains, pumps, transfer hoses, and other equipment that is difficult to sanitize. The survivability of ''Brettanomyces'' has also partly been attributed to its ability to form a [https://en.wikipedia.org/wiki/Biofilm biofilm] (in particular ''B. bruxellensis''). Microorganisms that can form a biofilm are more resistant to chemical cleaning agents and sanitizers than those that don't. ''Brettanomyces'' has therefore been identified as a significant contaminate for breweries and wineries. Oak barrels from wineries with unsanitary practices in particular have been identified as common contamination sites for ''B. bruxellensis''. ''Brettanomyces'' has also been isolated from olives, lemonade, and soft drinks, with ''B. anomalus'' and ''B. bruxellensis'' generally being much more frequently isolated than the other three species of ''Brettanomyces''. <ref name="smith_divol_2016">[http://www.sciencedirect.com/science/article/pii/S0740002016302659 Brettanomyces bruxellensis, a survivalist prepared for the wine apocalypse and other beverages. Brendan D. Smith, Benoit Divol. June 2016.]</ref>.
Unlike most genres of yeast, ''Brettanomyces'' has the characteristics of being very tolerant to high amounts of alcohol, a pH as low as 2 <ref>[http://www.winesandvines.com/template.cfm?section=news&content=141954 Wines and Vines. New Research on Role of Yeast in Winemaking; report on a presentation by David Mills and Lucy Joseph from UC Davis. 11/14/2014. Retrieved 08/16/2015.]</ref>, and low nitrogen sources <ref name="Schifferdecker"></ref>. Perhaps the most differentiating characteristic of ''Brettanomyces'' is its preference to ferment glucose in the presence of oxygen, which is the opposite preference in [[Saccharomyces]]. This was initially dubbed the "negative Pasteur effect" by Custers, and later the "Custers effect" <ref name="yakobson_introduction"></ref>.