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* The addition of hops in the starter wort will inhibit or kill some gram positive bacteria pathogens (''L. monocytogenes'' and ''S. aureus'') <ref name="Menz1">[http://www.ncbi.nlm.nih.gov/pubmed/22004814 Growth and survival of foodborne pathogens in beer. Menz G., Aldred P, Vriesekoop F . Oct 2011.]</ref><ref name="BryanMTF">[https://www.facebook.com/groups/MilkTheFunk/permalink/1104757552885791/?comment_id=1105118642849682&offset=0&total_comments=15&comment_tracking=%7B%22tn%22%3A%22R%22%7D Conversation with Bryan Heit on MTF regarding when it is safe to taste wild beer. 7/6/2015.]</ref>.
* A low pH is not the only requirement for making beer safe. A combination of alcohol, low pH, and hops will ensure that pathogens cannot grow (survival is another matter) <ref name="Bryan">[http://suigenerisbrewing.blogspot.ca/2014/02/fact-or-fiction-can-pathogens-survive.html ''Fact or Fiction? Can Pathogens Survive in Beer?'' Sui Generis Blog, by Bryan Heit.]</ref><ref>[http://www.ncbi.nlm.nih.gov/pubmed/20207437 The growth and survival of food-borne pathogens in sweet and fermenting brewers' wort. Menz G1, Vriesekoop F, Zarei M, Zhu B, Aldred P. May 2010.]</ref>.
* Two studies have shown that ''E. coli'' can survive in moderate strength beer for at least 28 days (more than 30 says days in one study) if the beer is stored cold (39-41°F or 4-5°C) <ref name="Menz1"></ref><ref>[http://www.ncbi.nlm.nih.gov/pubmed/24674433 Survival of foodborne pathogenic bacteria (Bacillus cereus, Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium, Staphylococcus aureus, and Listeria monocytogenes) and Bacillus cereus spores in fermented alcoholic beverages (beer and refined rice wine). Kim SA1, Kim NH, Lee SH, Hwang IG, Rhee MS. March 2014.]</ref>. Therefore, the wild culture should be stored at room temperature for a least a month before tasting. Additionally, the pH of the beer should be less than 4.5, and alcohol should be present for at least one month before tasting. The smell of feces or vomit indicates that these bacteria may be present; dump it out if so. <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/1104757552885791/?comment_id=1104851526209727&offset=0&total_comments=8&comment_tracking=%7B%22tn%22%3A%22R1%22%7D Conversation with Bryan Heit on MTF regarding when it is safe to taste wild beer. 7/5/2015.]</ref>.
* In unfermented wort, ''E. coli O157:H7'' and ''Salmonella Typhimurium'' were shown to grow at a pH of 4.3, but stopped growing at a pH of 4.0 <ref name="Menz1"></ref>. However, some of these food poisoning bacteria can survive the low pH of the stomach (~2.0), so relying on a low pH alone is not adequate. Bryan Heit recommends a pH of 4.5 or less, the use of well sanitized equipment, and monitoring the starter for the rapid onset of fermentation without putrid smells. Some oxidative yeasts that are the first "barriers" to bacterial growth may be inhibited at 4.0 pH <ref name="BryanMTF"></ref>.
* The risk of botulism toxin is extremely low, but not non-zero. Generally, ''C. botulism'' is not able to grow and produce toxin in low protein (non-meats) substances at a pH lower than 4.6 <ref>[http://www.ingentaconnect.com/content/iafp/jfp/1982/00000045/00000003/art00005 Toxin Production by Clostridium Botulinum in Media at pH Lower Than 4.6. Nobumasa, Tanaka. Journal of Food Protection®, Number 3, February 1982, pp. 214-284, pp. 234-237(4)]</ref><ref>[http://edis.ifas.ufl.edu/fs104 Preventing Foodborne Illness: Clostridium botulinum. University of Florida IFAS Extension. Retrieved 7/5/2015.]</ref>. However, proteins in the wort may allow growth even at a lower pH (studies have not been done on wort, only on meats) <ref name="BryanMTF"></ref>. The presence of more than 5% oxygen in the wort will also reduce the risk <ref>[http://www.ncbi.nlm.nih.gov/pubmed/15895734 Growth and toxin production by Clostridium botulinum in steamed rice aseptically packed under modified atmosphere. Kasai Y, Kimura B, Kawasaki S, Fukaya T, Sakuma K, Fujii T. May 2005.]</ref>.