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[[File:Heat sanitizing barrels.JPG|thumbnail|right|[https://www.ncbi.nlm.nih.gov/pubmed/25989358 Effects of heat sanitation results by Fabrizio et al (2015).]]]
Heat has been established as the most reliable way to sanitize surfaces, with ''Brettanomyces'' beginning to die at around 37°C and the complete thermal death of ''Brettanomyces'' has been reported to be 50°C for 5 minutes in wine <ref>[https://pubmed.ncbi.nlm.nih.gov/15996781/ Thermal inactivation of the wine spoilage yeasts Dekkera/Brettanomyces. José António Couto, Filipe Neves, Francisco Campos, Tim Hogg. 2005. DOI: 10.1016/j.ijfoodmicro.2005.03.014.]</ref><ref name="Nunes de Lima 2020">[https://www.sciencedirect.com/science/article/abs/pii/S0740002020302069 Survival and metabolism of hydroxycinnamic acids by Dekkera bruxellensis in monovarietal wines. Adriana Nunes de Lima, Rui Magalhães, Francisco Manuel Campos, José António Couto. 2020. DOI: https://doi.org/10.1016/j.fm.2020.103617.]</ref>. The complete thermal death of ''Brettanomyces'' in wines has been reported to be 50°C for 5 minutes. <ref>[https://pubmed.ncbi.nlm.nih.gov/15996781/ Thermal inactivation of the wine spoilage yeasts Dekkera/Brettanomyces. José António Couto, Filipe Neves, Francisco Campos, Tim Hogg. 2005. DOI: 10.1016/j.ijfoodmicro.2005.03.014.]</ref><ref name="Nunes de Lima 2020" />. Sanitizing barrels that are infected with ''Brettanomyces'' or other beer/wine spoilers is notoriously difficult, and some believe it to be impossible. While two previous studies ([http://www.ajevonline.org/content/62/4/519 Schmid et al. 2011] and [http://www.ccsenet.org/journal/index.php/jfr/article/view/24315 Barata et al. 2013]) found that steam was not effective at sanitizing oak, these studies have had their experimental designs criticized by more recent studies ([https://www.ncbi.nlm.nih.gov/pubmed/25989358 Fabrizio et al. 2015] and [http://www.ajevonline.org/content/early/2018/05/23/ajev.2018.18024 Cartwright et al. 2018]). For example, Schmid et al. (2011) inoculated oak chips with nutrient broth instead of using barrels that represented real-world conditions, and Barata et al. (2013) only applied steam for 10 minutes <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>.
In contrast, Fabrizio et al. (2015) and Cartwright et al. (2018) found that it is possible that steam is an effective way to kill all ''Brettanomyces'' in oak barrels that previously held ''B. bruxellensis'' inoculated wine. Fabrizio et al. (2015) proposed that the most effective and preferred method is to heat the inside of the oak barrel to at least 140°F (60°C) for 20 minutes with hot water or steam. This was demonstrated to be an effective way of killing ''Brettanomyces'' that was found growing as deep as 8 mm within the wood of 3-year old barrels infected with ''Brettanomyces''. Note that this might not be hot enough to kill other heat-tolerant microbes; however, these heat-tolerant species tend not to be able to survive in beer. Steam treatments that are higher in temperature and longer should not present any concerns to the barrels themselves; however, if hot water is used instead of steam then the longer the water is exposed to the barrel the more character from the barrel that gets removed by the water <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 name="Agnolucci_2017">[https://link.springer.com/article/10.1007/s11274-017-2345-z Brettanomyces bruxellensis yeasts: impact on wine and winemaking. Monica Agnolucci, Antonio Tirelli, Luca Cocolin, Annita Toffanin. 2017.]</ref>.