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Elliot Parcells & Josh Pohlmann from Bells Brewery tested the efficiency of various sanitizers to kill ''Lactobacillus'', ''Brettanomyces'', and ''Saccharomyces cerevisiae'' var. ''diastaticus''. The sanitizers tested were 100% ethanol, 70% ethanol, isopropyl alcohol, and iodophor at 25 ppm concentration (the recommended no-rinse concentration). With 15 seconds of exposure, both 100% ethanol and 70% ethanol showed no growth. At the maximum time tested, which was 90 seconds, iodophor still showed growth. They found that a concentration of 50 ppm concentration of iodophor at 2 minutes was enough concentration and time to kill ''Lactobacillus'', and 5 minutes for the yeast species tested at 50 ppm. At 75 ppm concentration of iodophor (which is the maximum concentration that is possible to achieve in water due to the equilibrium of free iodine <ref>[http://realbeer.com/jjpalmer/cleaning.html#iodo Palmer, John. A COMPLETE GUIDE TO CLEANING AND SANITATION. RealBeer.com website. Retrieved 07/09/2018.]</ref>), it took 2 minutes to kill all of the microorganisms tested. Across all of the tests, the yeast species were more resistant than the lactic acid bacteria species tested. The ethanol solution remained their preferred sanitizer for spray bottles despite its fast evaporation rate.
The methodology of this experiment has received some criticism that might invalidate its results. They diluted yeast/bacteria cultures on a 1:10 ratio into iodophor, thus diluting the iodophor below its recommended dilution and exposing it to concentrations of microbes far beyond what it was designed to kill. Testing the ability to sterilize a bulk solution does not translate to the ability of the sanitizer to sanitize trace surface microbes after proper cleaning <ref>[https://www.facebook.com/groups/MilkTheFunk/permalink/2172245389470330/?comment_id=2172685769426292&comment_tracking=%7B%22tn%22%3A%22R%22%7D Dr. Bryan Heit. Milk The Funk Facebook thread on an MBAA podcast about the efficacy of iodohor as a sanitizer. 07/10/2018.]</ref>.
See the full interview with Elliot and Josh on the [http://masterbrewerspodcast.com/096-efficacy-of-sanitizers-in-the-brewery MBAA Podcast].