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  • 1.  Michael Barney Research

    Posted 07-03-2025 11:29

    Hoping someone with a better memory than me who can point me in the right direct.  I have a vague recollection of reading a paper by or co-authored by Michael Barney during his years at Miller.  The paper was about the potential for pathogens in atypical beer products.  If my memory is correct, these beers did contain alcohol and some may have contained fruit.  I have looked for this paper multiple times over a couple of years and always come up with nothing.

    The reason for the question has to do with an obvious omission from the trial conduced by the group at Cornell in their paper oddly titled "Survival of Foodborne Pathogens in Low and Nonalcoholic Craft Beer" where commercially sourced cans of Genesse were adjusted for the study before being inoculated with pathogens. If memory serves me correctly, the paper I am seeking would add to the current discussion about the potential for pathogens in beer.

    One thing that has been bugging me is the title of the paper from the group at Cornell.  Aside from the title, the word craft only appears three times in the publication.  And in all cases, craft is generically used without reference to describe a segment of the industry not addressed by the research or the citations in the publication.  That just seems odd, but I digress.

    What seems to have been left out of the study was a control beer. It's sort of implied that the pathogens would not have faired well in beer with more than 2.5% ABV, but that's a stretch in the absence of supporting data. In fact, the introduction contains some interesting background that has more or less been ignored by most because headlines are more often read than papers. The authors wrote "It has also been shown pathogens can survive in alcoholic beveragesBacillus cereus and E. coli O157:H7 have been shown to survive in beer and refined rice wine (Kim et al., 2014). Bacillus cereus spores were also detected in finished beer when held at warm temperatures (4–60°C) for more than 4 h. E. coli O157:H7 and Salmonella Typhimurium cannot grow in mid-strength to full-strength beers. However, they can survive for more than 30 days when held at 4°C (Menz et al., 2011). E. coli spp. and coliforms have been isolated in draught beer, and other beer containers (Schindler and Metz, 1990). There have been reports of botulism associated with drinking the fermented alcoholic beverage Pruno made from potatoes (Briggs et al., 2013)." What would our industry do if this trial was repeated with something like the best selling light beer in the US and the results showed that aerobically held samples of X Light inoculated with fecal microflora were found to contain viable cells for several weeks?

    If any one out there remembers the paper from Michael Barney and others, please help a nerd out!

    Have a safe and happy Independence Day weekend!



    ------------------------------
    Ashton Lewis
    Manager of Training and Technical Support
    RahrBSG
    MBAA District Great Plains, Technical Chair
    Springfield, Missouri
    (417) 830-2337
    ------------------------------


  • 2.  RE: Michael Barney Research

    Posted 07-07-2025 16:48

    Hi Ashton,

    Have you seen this article?

    https://eprints.nottingham.ac.uk/74590/1/Bartlett%20Connor%2020402412%20Corrections%201.pdf

    Dana



    ------------------------------
    Dana Johnson He/Him
    Technical Manager, Craft Brewing
    Diversey - A Solenis Company
    Henderson, CO
    800.233.1000
    ------------------------------



  • 3.  RE: Michael Barney Research

    Posted 07-08-2025 16:08

    Hi Dana,

    I had not previously seen this thesis.  Lots of great information in this.  Thank you for sharing!

    Cheers,

    Ashton



    ------------------------------
    Ashton Lewis
    Manager of Training and Technical Support
    RahrBSG
    MBAA District Great Plains, Technical Chair
    Springfield, Missouri
    (417) 830-2337
    ------------------------------



  • 4.  RE: Michael Barney Research

    Posted 07-17-2025 15:37

    Hi Ashton-

    I searched the internet and I couldn't find the paper you were referencing originally. I am interested in reading it if you find it! 

    Thanks for the other paper, Dana.

    Cheers,

    Wade



    ------------------------------
    Wade Begrow
    Microbiology and Food Safety Manager
    Founders Brewing Company
    Grand Rapids MI
    ------------------------------



  • 5.  RE: Michael Barney Research

    Posted 07-18-2025 16:23
    I worked with Mike Barney and this was his response:

    Regarding the discussion, I don’t know what paper he is referring to, but the issue is more complex than his discussion. He is omitting pH, anaerobic environment, heat disinfection, sterile filtration in addition to lack of microbial nutrients and addition of hops. It is a complex argument for getting pathogens to affect beers. No doubt one could create a beer that pathogens could survive and potentially grow in like many other food products. Then it becomes an issue on how to disinfect/stabilize

    Sent from my iPhone




  • 6.  RE: Michael Barney Research

    Posted 07-21-2025 12:47
    Nick, thank you for reaching out to Michael Barney about my question.  I believe Andrew Fratianni found the paper I was seeking.

    I wish there were more discussion of this topic on Ask the Brewmasters. My original post from June 2, 2025 referenced the FDA's fruit juice pasteurization requirements that were implemented following the 1996 E. coli outbreak linked to Odwalla apple juice. The intent of my post was to generate some noise to challenge the message being sent to brewers and the general public about this subject.

    Combining the FDA juice pasteurization methodology with what I have read about the fate of pathogens inoculated into NABLABs, it sure seems that thermal methods that address the risk of spoilers will knock out any pathogens before spoilers are killed. It's difficult to find a single source that presents D-values for all relevant organisms in beer, but the following data set pulls together information from three sources. While not directly comparable due to differences in the reference temperatures for the D-values, the data show that beer spoilers are generally more thermotolerant than the pathogens listed.

    The acid-adapted E. coli O157:H7 strains from the fruit juice study are particularly noteworthy. Acid adaptation significantly increases thermal resistance, and in this study, the organisms were harvested from stationary-phase cultures prior to thermal challenge. Because these acid-adapted E. coli strains have relatively high D-values, the FDA references this study in its guidance to juice processors when the most likely pathogen is unknown. Even so, the D-values are still significantly lower than those of common beer spoilers.


    Organism
    Type
    Media
    Temperature
    (C)
    D-value
    (min)
    Source
    L. delbrueckii
    Spoiler
    Beer @ 5% ABV
    51.1
    11.2 
    a
    P. acidilacti
    Spoiler
    Beer @ 5% ABV
    49.2
    3.5
    a
    E. coli 0157:H7
    Pathogen
    Beer @ 5% ABV
    50.8
    0.6
    a
    S. typhimurium
    Pathogen
    Beer @ 5% ABV
    49.2
    0.5
    a






    L. delbrueckii
    Spoiler
    AF Beer @ < 0.5% ABV
    53.1
    10.9
    a
    P. acidilacti
    Spoiler
    AF Beer @ < 0.5% ABV
    55.0
    9.6
    a
    E. coli 0157:H7
    Pathogen
    AF Beer @ < 0.5% ABV
    55.0
    1.4
    a
    S. typhimurium
    Pathogen
    AF Beer @ < 0.5% ABV
    53.1
    1.3
    a






    S. cerevisae
    Spoiler
    Tomato Juice @ pH 4.5
    57
    15
    b
    S. cerevisae
    Spoiler
    Apple Juice @ pH 3.9
    57
    9
    b






    E. coli 0157:H7
    (acid adapted)
    Pathogen
    Apple Juice @ pH 3.9
    56
    7.0
    c
    E. coli 0157:H7
    (stationary phase)
    Pathogen
    Apple Juice @ pH 3.9
    56
    4.1
    c






    E. coli 0157:H7
    (acid adapted)
    Pathogen
    Grape Juice @ pH 3.9
    56
    6.1
    c
    E. coli 0157:H7
    (stationary phase)
    Pathogen
    Grape Juice @ pH 3.9
    56
    4.0
    c
    Sources:


    Cheers,
    Ashton






  • 7.  RE: Michael Barney Research

    Posted 07-22-2025 09:13
    Andy,

    I was looking back at this email this morning and spotted one error in the table (the last E. coli data point should read "Stationary Phase").  This has been corrected below.  If this has already been published, no worries.

    Organism
    Type
    Media
    Temperature
    (C)
    D-value
    (min)
    Source
    L. delbrueckii
    Spoiler
    Beer @ 5% ABV
    51.1
    11.2 
    a
    P. acidilacti
    Spoiler
    Beer @ 5% ABV
    49.2
    3.5
    a
    E. coli 0157:H7
    Pathogen
    Beer @ 5% ABV
    50.8
    0.6
    a
    S. typhimurium
    Pathogen
    Beer @ 5% ABV
    49.2
    0.5
    a






    L. delbrueckii
    Spoiler
    AF Beer @ < 0.5% ABV
    53.1
    10.9
    a
    P. acidilacti
    Spoiler
    AF Beer @ < 0.5% ABV
    55.0
    9.6
    a
    E. coli 0157:H7
    Pathogen
    AF Beer @ < 0.5% ABV
    55.0
    1.4
    a
    S. typhimurium
    Pathogen
    AF Beer @ < 0.5% ABV
    53.1
    1.3
    a






    S. cerevisae
    Spoiler
    Tomato Juice @ pH 4.5
    57
    15
    b
    S. cerevisae
    Spoiler
    Apple Juice @ pH 3.9
    57
    9
    b






    E. coli 0157:H7
    (acid adapted)
    Pathogen
    Apple Juice @ pH 3.9
    56
    7.0
    c
    E. coli 0157:H7
    (stationary phase)
    Pathogen
    Apple Juice @ pH 3.9
    56
    4.1
    c






    E. coli 0157:H7
    (stationary phase)
    Pathogen
    Grape Juice @ pH 3.9
    56
    6.1
    c
    E. coli 0157:H7
    (stationary phase)
    Pathogen
    Grape Juice @ pH 3.9
    56
    4.0
    c
    Sources:





  • 8.  RE: Michael Barney Research

    Posted 07-19-2025 08:36

    Hi Ashton,

    This is what I have been able to find.  Maybe this is what you had in mind.

    Friedman, D.E., Patten, K.A., Rose, J.B. and Barney, M.C. (1997) 'The potential for cryptosporidium parvum oocyst survival in beverages associated with contaminated tap water', Journal of Food Safety, 17(2), pp 125-132.  Available at:  doi.org/10.1111/j.1745-4565.1997.tb00181.x

    Andrew 



    ------------------------------
    Andrew Fratianni, Dipl. Brew.
    Sr. Enzyme Application Specialist
    Brewing & Distilling Enzymes
    IFF Health & Biosciences
    andrew.j.fratianni@iff.com
    ------------------------------



  • 9.  RE: Michael Barney Research

    Posted 07-21-2025 09:52
    Thank you, Andrew!  I do believe that is the paper.  I knew if was from the 1990's and not specific to normal beer.  I have not been able to read more than the abstract without paying for a reprint.  If you have found the full paper, a PDF link would be most appreciated.

    Cheers,
    Ashton