Changes

Up until recently, ''Brettanomyces'' has been thought to occur naturally on the skins of fruit such as apples and grapes. However, ''Brettanomyces'' has rarely been identified on the skins of fruit <ref>[https://onlinelibrary.wiley.com/doi/full/10.1002/jib.154 Lentz, M., Putzke, T., Hessler, R. and Luman, E. (2014), Genetic and physiological characterization of yeast isolated from ripe fruit and analysis of fermentation and brewing potential, J. Inst. Brew., 120: 559– 564. DOI: 10.1002/jib.154.]</ref><ref name="smith_divol_2016"></ref><ref name="Schifferdecker" />. It is also thought to disperse via insects such as bees and fruit-flies (called "vectors" in the scientific literature), similar to how ''Saccharomyces'' travels, although direct evidence for this is lacking <ref>[https://youtu.be/G2nhUM5PIrg?t=309 Dr. Bryan Heit. BotB - Where (Do) The Wild Brettanomyces Roam?. ~5 mins in. Retrieved 07/10/2022.]</ref><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><ref>[https://www.ncbi.nlm.nih.gov/pubmed/18077036 Survival patterns of Dekkera bruxellensis in wines and inhibitory effect of sulphur dioxide. f Barata A, Caldeira J, Botelheiro R, Pagliara D, Malfeito-Ferreira M, Loureiro V. 2008.]</ref><ref>[https://www.ncbi.nlm.nih.gov/pubmed/12892920 Spoilage yeasts in the wine industry. Loureiro V, Malfeito-Ferreira M. 2003.]</ref>. For example, an ongoing survey of wild yeasts in most of the US which isolated nearly 2,000 isolates with 262 unique species has not yet found a single occurrence of ''Brettanomyces'' in the wild (so far they have only surveyed non-human inhabited wild areas of the US and Alaska; substrates sampled included leaves, soil, bark, moss, mushrooms, needles, pine cones, twigs/wood, and other plant matter) <ref>[https://www.biorxiv.org/content/10.1101/2021.07.13.452236v1 Substrate, temperature, and geographical patterns among nearly 2,000 natural yeast isolates. William J. Spurley, Kaitlin J. Fisher, Quinn K. Langdon, Kelly V. Buh, Martin Jarzyna, Max A. B. Haase, Kayla Sylvester, Ryan V. Moriarty, Daniel Rodriguez, Angela Sheddan, Sarah Wright, Lisa Sorlie, Amanda Beth Hulfachor, Dana A. Opulente, Chris Todd Hittinger. bioRxiv 2021.07.13.452236; doi: https://doi.org/10.1101/2021.07.13.452236.]</ref>. ''Brettanomyces'' is known to be difficult to grow in a lab due to slow growth, specific nutrient requirements, or perhaps because of a "VBNC" state (see [[Wild_Yeast_Isolation#Wild_Brettanomyces|Wild ''Brettanomyces'']] for more information). More recently, techniques have been invented to more easily isolate and grow ''Brettanomyces''<ref>[https://www.sciencedirect.com/science/article/pii/S0944501306000231?via%3Dihub Development of an enrichment medium to detect Dekkera/Brettanomyces bruxellensis, a spoilage wine yeast, on the surface of grape berries. Vincent Renouf, Aline Lonvaud-Funel. 2007. DOI: https://doi.org/10.1016/j.micres.2006.02.006.]</ref><ref>[https://www.frontiersin.org/articles/10.3389/fmicb.2019.00415/abstract Occurrence of Brettanomyces bruxellensis on grape berries and in related winemaking cellar. Francesca Comitini1, Lucia Oro, Laura Canonico, Valentina Marinelli, Maurizio Ciani. 2019. DOI: 10.3389/fmicb.2019.00415.]</ref>. There is more evidence that the natural habitat of ''Brettanomyces'' might actually be the root systems of certain plants, known as the [https://www.nature.com/scitable/knowledge/library/the-rhizosphere-roots-soil-and-67500617/ "rhizosphere"]. The rhizosphere refers to the complex symbiotic community of microbe populations that live on or around the root system of plants. Wild strains of ''Brettanomyces'' have been found in the root systems of dill, common beans, sunflowers, maize, corn, jute, cassava, and grey mangroves found in the estuaries of Indonesia <ref>[https://onlinelibrary.wiley.com/doi/abs/10.1111/aab.12309 Weisany, W., Raei, Y., Salmasi, S., Sohrabi, Y. and Ghassemi-Golezani, K. (2016), Arbuscular mycorrhizal fungi induced changes in rhizosphere, essential oil and mineral nutrients uptake in dill/common bean intercropping system. Ann Appl Biol, 169: 384-397. https://doi.org/10.1111/aab.12309.]</ref><ref>[https://archive.aessweb.com/index.php/5003/article/view/3333 I.O, S. ., & G.P, O. . (2012). Diversity of Fungal Populations in Soils Cultivated With Cassava Cultivar TMS 98/0505. Journal of Asian Scientific Research, 2(3), 116–123. Retrieved from https://archive.aessweb.com/index.php/5003/article/view/3333.]</ref><ref>[https://www.ajol.info/index.php/swj/article/view/149513 Rhizosphere and non-rhizosphere soil mycoflora of Corchorus olitorius (Jute). G.S. Olahan, I.O. Sule, T Garuba, Y.A. Salawu. Science World Journal. 2016.]</ref><ref>[https://ojs.unud.ac.id/index.php/jbb/article/view/36023 NOERFITRYANI, Noerfitryani; HAMZAH, Hamzah. THE EXISTENCE OF ENTOMOPATHOGENIC FUNGI ON RICE PLANTS RHIZOSPHERE. International Journal of Biosciences and Biotechnology, p. 12-24, dec. 2017. ISSN 2655-9994. doi: https://doi.org/10.24843/IJBB.2017.v05.i01.p02.]</ref><ref>[https://www.sciencedirect.com/science/article/abs/pii/S2452219818300259 Marcela Sarabia, Saila Cazares, Antonio González-Rodríguez, Francisco Mora, Yazmín Carreón-Abud, John Larsen, Plant growth promotion traits of rhizosphere yeasts and their response to soil characteristics and crop cycle in maize agroecosystems, Rhizosphere, Volume 6, 2018, Pages 67-73, ISSN 2452-2198, https://doi.org/10.1016/j.rhisph.2018.04.002.]</ref><ref>[https://www.sciencedirect.com/science/article/abs/pii/S1049964419303238 Nivien A. Nafady, Mohamed Hashem, Elhagag A. Hassan, Hoda A.M. Ahmed, Saad A. Alamri. The combined effect of arbuscular mycorrhizae and plant-growth-promoting yeast improves sunflower defense against Macrophomina phaseolina diseases. Biological Control. Volume 138, 2019, 104049. ISSN 1049-9644, https://doi.org/10.1016/j.biocontrol.2019.104049.]</ref><ref>[http://ejurnal.its.ac.id/index.php/sains_seni/article/view/5613 Isolation and Characterization of Yeast from Rhizosphere Avicennia Marina Wonorejo. Sitatun Zunaidah, Nur Hidayatul Alami. 2014. DOI: 10.12962/j23373520.v3i1.5613.]</ref>. See Dr. Bryan Heit's video [https://www.youtube.com/watch?v=G2nhUM5PIrg "Where (Do) The Wild Brettanomyces Roam?"] and [https://www.facebook.com/groups/MilkTheFunk/posts/5940213029340195 his comments in Milk The Funk], as well as [https://www.youtube.com/watch?v=BrR7G_YyfmA "Philip Poole. Plant Control of the Rhizosphere Microbiome"]. For documented isolation attempts from plant rhizospheres, see [[Wild_Yeast_Isolation#Wild_Brettanomyces|Wild Yeast Isolation]].

''Brettanomyces'' is commonly isolated from the surface of wood structures within breweries, wineries, and sometimes cideries (although the median occurrence of ''Brettanomyces'' in barrels may be very low to none within a given winery or brewery depending on their hygiene and other factors <ref>[https://link.springer.com/article/10.1007/s00217-011-1523-8 Guzzon, R., Widmann, G., Malacarne, M. et al. Survey of the yeast population inside wine barrels and the effects of certain techniques in preventing microbiological spoilage. Eur Food Res Technol 233, 285–291 (2011). https://doi.org/10.1007/s00217-011-1523-8.]</ref><ref>[https://agris.fao.org/agris-search/search.do?recordID=IT2007601151 Fontanot, S.; Ninino, M.E.; Comi, G.; Elimination of Dekkera/Brettanomyces from barriques of the Italian CDO Isonzo area. Controlled Designation of Origin; Friuli-Venezia Giulia. 2006.]</ref>). 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. ''Brettanomyces'' has been easily cultured from within the wood of oak barrels up to 4 mm into the wood, and occasionally as deep as 5 to 8 mm, depending on the age and variety (slightly higher populations tend to survive in French oak over American oak, and one study found that the ''Brettanomyces'' was able to penetrate the French oak barrels up to 8 mm, while only penetrate American oak barrels up to 4 mm) of the barrel <ref name="Agnolucci_2017" /><ref name="Cartwright_2018">[http://www.ajevonline.org/content/early/2018/05/23/ajev.2018.18024 Reduction of Brettanomyces bruxellensis Populations from Oak Barrel Staves Using Steam. Zachary M. Cartwright, Dean A. Glawe, Charles G. Edwards. 2018. DOI: 10.5344/ajev.2018.18024.]</ref>, with the highest concentration of surviving cells being at the top staves where oxygen is more accessible (although Cartwright et al. found the opposite was true, perhaps due to methodology of sampling or a difference in SO₂ concentrations). Some strains are able to utilize the cellulose of the wood as a carbon source, and occasionally form pseudohyphae within the wood which expands the surface area of the cells allowing them more access to nutrients and allowing them to survive in nutrient deficient environments <ref name="Cartwright_2018" />. Ozone gas has been shown to be an effective way to kill ''Brettanomyces'' that is buried in the wood of oak barrels, but the ozone must be applied for an adequate time to allow for the ozone to diffuse into the oak. Ozone has also been shown to be an effective way of greatly reducing but not completely eliminating the number of ''Brettanomyces'' on wine grapes. Liquid ozone has been shown to be less effective at eliminating ''Brettanomyces''. Heating the inside of the oak barrels to 60°C for 20 minutes with hot water or steam has also been found to be an effective way of killing ''Brettanomyces'' within the wood of barrels (see [[Barrel#Sanitizing|Barrel Sanitation]] for information on pasteurizing barrels) <ref>[https://www.ncbi.nlm.nih.gov/pubmed/25989358 Heat inactivation of wine spoilage yeast Dekkera bruxellensis by hot water treatment. Fabrizio, Vigentini, Parisi,Picozzi, Compagno, Foschino. 2015.]</ref><ref>[https://www.sciencedirect.com/science/article/pii/S1466856417310068 Control of Brettanomyces bruxellensis on wine grapes by post-harvest treatments with electrolyzed water, ozonated water and gaseous ozone. Francesco Craveroa, Vasileios Englezos, Kalliopi Rantsiou, Fabrizio Torchio, Simone Giacosa, Susana Río Segade, Vincenzo Gerbi, Luca Rolle, Luca Cocolin. 2018. DOI: https://doi.org/10.1016/j.ifset.2018.03.017.]</ref>. 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 [[Quality_Assurance#Biofilms|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'' is also commonly found in sherry, and is found (although only rarely) in olive production, lemonade, kombucha, yogurt, pickles, and soft drinks. ''B. anomalus'' and ''B. bruxellensis'' are generally found much more commonly 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>.