Poindexter said:
Can you get a sample with out contaminating the rest? My current best hypothesis is a "new" to your area bug the muni plant isn't getting. A spore former that gets activated in the wort boil and then can survive in an alcohol environment. Don't have a name on the tip of my tongue.
If your beer smells, looks, _and_ tastes right today...
If it were a case of some "super" bug going around San Antonio, don't you think that there would be other adverse effects of such a bug. Like people getting sick with strange undocumented symptoms. Or pets, livestock, wildlife or plantlife also showing some signs of this bacteria. Or, other foods spoiling?
Realistically, in all likelihood, this is a problem isolated to the one, possibly two, brewers that are experiencing the problem. And, the problem is either due to an infection (Brettanomyces, Lactobacillus or Pediococcus) or a procedural step that is either being done improperly or omitted altogether.
First, replace all plastic/vinyl hoses and racking canes with new thoroughly sterilized hoses and canes. Carefully clean and sanitize all spigots. If you use an aeration systems. Replace the parts you can, and soak everything in sanitizer. Immersion chiller (though you shouldn't have to) give it a good scrub with dish soap and soak in sanitizer prior to chilling wort. If you're using a kit, purchase it from a different location and brew a fairly easy recipe such as an IPA or APA and
DON'T use liquid yeast ... pitch two (one should do it but be safe) packets of Safale-05.
I would suggest eliminating all variables regarding sanitation (brew outside, use spring water, etc.) that you can think of. Elminating one variable at a time will help you to figure out exactly what went/is going wrong, but what good does it do you to know that some spigot wasn't being sanitized and in the course you lost 3 more batches. Elminate everything and establish new procedures. If you eliminate all the variables regarding sanitation then you'll know its something procedural.