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* Two studies have shown that ''E. coli'' can survive in moderate strength beer for at least 28 days (more than 30 says 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>. Since the beer of a starter can be decanted, adding enough lactic acid to get the starter wort down to 4.0 won't effect the taste of the final beer, and is a a good extra precaution.
* The risk of botulism toxin is non-existent due to ''C. botulism'' being unable 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>. 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>.
* In the words of Bryan Heit from Sui Generis Blog: "''If you have an immunodeficiency or are immunosuppressed: Obviously, don't take medical advice off the internet. Talk to your MD to see if you are at risk of infection - especially if you're condition/treatment increases your risk of fungal infections. If so, or if you are concerned, stick to beers that are fermented using commercial strains of Saccharomyces yeast.''" <ref name="Bryan"></ref>