infected beer, not sure why

Greetings,

I've been brewing for 2 and half years and in that time I've made 30 or so batches of really nice, drinkable beer. I was kegging a couple of beers this evening; a west coast red ale and a Belgian Golden strong ale. I thiefed a bit of the west coast red out of the bucket for a gravity reading and to take a quick taste. The beer looked a beautifully bright clear beer, however it smelled bad and tasted God awful. Like band-aids, kind of rubbery too, like licking a truck tire or something. I couldn't bring myself to taste it again. Needless to say I dumped it.

Since I've always been really conscientious of sanitation, this really took me by surprise. I do not want this to happen again. Anyone have any ideas on exactly went wrong? I fermented the beer in a plastic bucket for about 3 weeks. The FG came out about right. The bucket had the dried yeast ring around the top and the there was a good yeast cake at the bottom. Looking in my notes the bubbling from the blowoff hose began about 6 hours after pitching. For those reasons I'm thinking this infection came after the first 5 or 6 days of fermentation.

Any thoughts or ideas that I need to investigate further would be really helpful.

Chris

"Band-aids" and "rubbery" don't necessarily mean infection. It could be a couple of things- chlorine in the brewing water for one. Or a very stressed yeast due to a high temperature fermentation.

I'd still consider the fermenter it was in to be "contaminated" and bleach bomb it if it's glass and do my best to figure out if it was contamination or not.

If it's clear, and looks ok, I'd lean towards the stressed yeast or a change in brewing water. If it's sort of muddy looking and gets worse with time, then I'd say it is an infection.

The beer was clear and looked great so it may not be an infection. As far as water, I run my water through a charcoal filter for the chlorine and then add Campden tablets (1/4 per 5 gallons of brewing water) to my HLT for the chloramine. I don't think the yeast was stressed, but maybe. The temperature was a bit warm but not too out of line (72-74 deg F).

What does the other beer taste like? You might have mixed up your strains.

If you're absolutely sure that it was an infection and 100% positive you are using proper Aseptic technique then here's how I would go about it:

Inspect the fermentor, look for cracks, nicks, or any type of tiny little scratches where you might be able to trap bacteria. If you find any, regardless if you determine it as the origin of contamination, I would replace it. Check the bucket-valve too and particularly its gasket.

If you're positive the fermentor was clean, I would check any of the things you used to transfer your cooled wort. If your wort was cooled in the bucket, then inspect your wort chiller. In my experience, most home-breweries with infections have contamination origins in wort chilling. It's where the wort lives, at the worst possible temperatures, for the longest amount of time. Additionally, depending on the type of chiller you are using, you could be creating a perfect place for infection. Interestingly, a major factor in cooling efficiency, surface area, is also a major factor in promoting cell growth. Surface area increases the locations that bacteria can nucleate upon and create colonies. Unfortunately the smallest infections are the hardest to find. But I don't believe you have an infection. Just to make sure, boil your entire chiller in the hot wort during the final fifteen minutes of your brew, or run hot water (170F or above) through it backwards and forwards before chilling.

If you are sure it wasn't your chilling system, then it's your pump. I take apart my pump after every brew and put its parts away dry, then sanitize before use. At the end of the day, infection could have come from anywhere. A skin flake from your hands, your nose dripped something, a microscopic spore carrying alien bacteria for that matter, who knows. If you stay clean this should not repeat itself but every couple of years or so. You already dumped it, so there's no saving it now.

I will however say that a few things about your post, lead me to believe that you do not have an infection. Infections finish tart, and dry. Gravities are much lower, sometimes below 1.000 SG, from many infections. Also, many infections create a pellicle instead of the delicious krausen. If you've never had an infection, the pellicle is a waxy, dusty looking film that tends to have large, filmy bubbles. The pellicle "protects" the harmful bacteria from oxygen. And might take six months or two years or more to drop. You can drink "infected" beer, you just have to wait. Forever. I am probably not the only brewer that believes that any beer (including the band-aid, horse-blanket, latex glove flavored beers) will eventually become very complex and delicious beers with time. Or at least ridiculously delicious malt vinegar.

So my suspicion is not infection...

I believe you are describing the tastes of phenols, which are sometimes attributed to bacterial contamination, but usually they are from not rinsing your equipment thoroughly after sanitizing with bleach. Also, phenols can be leached from grain husks either by over-milling them or from sparging with too much liquor. If you are doing a steeped-extract, then your water was too hot, or you left your steeping grains in too long. It doesn't sound like your messing up your processes too much, but is it possible that you mixed up the yeast starters and inadvertently, fermented incorrectly, or you fermented too hot for the strain, or you pitched a bad, or mislabeled strain? What was your fermentation temp target and actual? I have tasted phenols from hot ferments "without infection" and they can taste almost exactly like "infections" but without the tartness, or sourness (not all infections taste tart, but I would say most do, and (not scientific,) the five or so I've tasted, were all very tart).

Could you have mixed up the yeasts? What were the yeast strains and temps?

I was using White Labs 001 standard California yeast strain. I fermented at 72 to 73 degrees. I'm sure I didn't mix the strains up as I didn't have any other strains at home at that time. I use an immersion chiller and always drop it in the kettle 15 minutes before knockout. I use starsan sanitizer and not bleach. Thanks for your input. I have a few more things to think about.

do you ferment in a temperature controlled fridge?

Nope, this was fermented in my closet.

If you have any of the beer left, or even a few specks of trub, or even just a thorough (sterile q-tip) swabbing of the brewery equipment and take two packages of plain gelatin, Knox or Jello work just fine, and some wort (1.020 gravity) and put them in your pressure cooker (or steam them over 1" H20, with lid) for 15 minutes. Then pour the mix into shallow plates and cover it with saran wrap. Petri dishes are a better choice, but you might need to order those online. Leave the stuff ontop of your fridge over night and post a picture of what grows. It should look like this:



If it looks like pretty much anything else (reddish color, furry tops, greenish color, tiny blobs, flakes, specks, whatever) then you cultured something else.

When pouring sterile gelatin onto sanitized sterile plates, make sure you aren't breathing, that there's no fans or blowers on, and do a lot of plates (just in case you start culturing your nose bacteria) and make sure you pay attention to the sterility of the swab, or trub or whatever your source is.

It may not even be worth all that trouble, but if you get a second infection, save it.

Thanks for the advice. I will definitely do that if it happens again. For the time being I'll use my 6 gallon better bottles for primary.

chrishobza said:

Nope, this was fermented in my closet.

Click to expand...

maybe the temps got up into the high 70's and you got some off flavors from that?