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Nothing Harmful Grows in Beer

Nothing Harmful Can/Will Grow in Beer

The reason nothing harmful can/will grow in beer is because beer is acidic with a pH ranging 3.5 – 4.0.

Leinenkugel's Red Lager was tested and it got a pH reading of 4.1.

If you visit the CDC's pdf here and look at pages 24 and 25 it lists the pH required for known pathogens to grow. As the pH of beer falls outside of this nothing harmful can/will grow in beer. While this isn't a reference to a specific page that says "Nothing Harmful Can/Will Grow in Beer", it explains why this is true.

In another study, worth noting in this study the organisms are added to the beer after it has already been fermented, and those organisms did not survive. So, if your bottle has a population of e. coli then it is similar to these experiments. Also, they seem to be talking about how much survives in beer, not growth in beer. And of course, most things are easily destroyed by boiling. Here is another abstract, they don't cover all pathogens, rather just common ones.

Department of Pathology, Medical College of Wisconsin, Milwaukee; an in vitro study was undertaken to determine the potential for survival of enteric pathogens in common drinking beverages. Three carbonated soft drinks, two alcoholic beverages, skim milk, and water were inoculated with Salmonella, Shigella, and enterotoxigenic Escherichia coli, and quantitative counts were performed over 2 days. Our studies showed poorest survival of all three organisms in wine, and greatest growth in milk and water. Beer and cola allowed survival of small numbers of Salmonella and E. coli at 48 h, whereas sour mix and diet cola were sterile by 48 h. Survival features may correlate with pH of the beverages. These observations may be useful in guiding travellers for appropriate beverage consumption while visiting areas endemic for "traveller's diarrhea."