Post-boil, pre-fermentation infections?

[jcp]

Hey, everyone.

I think that if you brew long enough, you start to encounter the same problems, over and over. Getting rid of those problems (i.e. finding out what about your process needs to change) becomes something of an obsession. Me? I've had a series of them:

• Incomplete fermentations. Solution: stop setting my fermentation chamber to such a low temperature.
• Lacto infections. Solution: replace all plastic gear, boil hop bags for 15 minutes before dry-hopping.
• Oxidation. Solution: Don't agitate bottles, don't store bottles in a place with extreme temperatures (too hot) or extreme temperature swings (light shining on boxes)

What's my latest though? I think I am dealing with persistent wild yeast infections. Here's my process:

• Mash, sparge, boil as normal
• Immersion chiller goes into the boil 15 minutes before flame-out
• At end of boil, cover boil pot with foil, fire up recirculation pump for whirlpool. All tubing is sanitized (and is probably re-sanitized by circulating the near-boiling wort)
• Once temperatures are down to below pitching temps, disconnect and drain into sanitized plastic fermenter.
• Move fermenter inside to continue process
• Use sanitized Thief to pull wort sample, put into plastic beaker, get hydrometer reading
• Put hydrometer sample into clean, sanitized jelly jar and lid up.
• Add yeast to fermenter, lid up, move to fermentation chamber. Temp probe is on the outside of the fermenter, covered in insulation.

The sample is kept in a warm (70-75F) cabinet, and typically begins to show signs of spontaneous infection anywhere between 36 and 48 hours. Only once did the sample show no signs of infection for a full week.

The infection starts as a thin foam ring around the edge of the glass, followed by what looks like a thin kreusen, with bubbles and what look like yeast rafts. If allowed to go for a full week, the wort becomes cloudy.

The sample smells ... dank. Dirty and earthy, almost like spoiled vegetables. When poured out, the wort isn't thick and ropey, so this isn't pedio, I don't think.

I really have no idea what I might be doing wrong, or how I can make things better. I've covered the pot, once the boil is finished, to minimize air-transfer, and lower the chance of wild yeast landing in the pot. It's possible that yeast are finding their way into the fermenter, when I transfer, but that doesn't take any more than a few minutes. I suppose I could move the boil pot inside and transfer, there, but that would be difficult, given as it's still connected to the recirculation pump.

What's happening here, folks? Has anyone dealt with anything similar? If so, how did you fix it?

 

[SEABrewer]

Hey, everyone. I think that if you brew long enough, you start to encounter the same problems, over and over. Getting rid of those problems (i.e. finding out what about your process needs to change) becomes something of an obsession. Me? I've had a series of them: [*]Incomplete fermentations. Solution: stop setting my fermentation chamber to such a low temperature. [*]Lacto infections. Solution: replace all plastic gear, boil hop bags for 15 minutes before dry-hopping. [*]Oxidation. Solution: Don't agitate bottles, don't store bottles in a place with extreme temperatures (too hot) or extreme temperature swings (light shining on boxes) What's my latest though? I think I am dealing with persistent wild yeast infections. Here's my process: [*]Mash, sparge, boil as normal [*]Immersion chiller goes into the boil 15 minutes before flame-out [*]At end of boil, cover boil pot with foil, fire up recirculation pump for whirlpool. All tubing is sanitized (and is probably re-sanitized by circulating the near-boiling wort) [*]Once temperatures are down to below pitching temps, disconnect and drain into sanitized plastic fermenter. [*]Move fermenter inside to continue process [*]Use sanitized Thief to pull wort sample, put into plastic beaker, get hydrometer reading [*]Put hydrometer sample into clean, sanitized jelly jar and lid up. [*]Add yeast to fermenter, lid up, move to fermentation chamber. Temp probe is on the outside of the fermenter, covered in insulation. The sample is kept in a warm (70-75F) cabinet, and typically begins to show signs of spontaneous infection anywhere between 36 and 48 hours. Only once did the sample show no signs of infection for a full week. The infection starts as a thin foam ring around the edge of the glass, followed by what looks like a thin kreusen, with bubbles and what look like yeast rafts. If allowed to go for a full week, the wort becomes cloudy. The sample smells ... dank. Dirty and earthy, almost like spoiled vegetables. When poured out, the wort isn't thick and ropey, so this isn't pedio, I don't think. I really have no idea what I might be doing wrong, or how I can make things better. I've covered the pot, once the boil is finished, to minimize air-transfer, and lower the chance of wild yeast landing in the pot. It's possible that yeast are finding their way into the fermenter, when I transfer, but that doesn't take any more than a few minutes. I suppose I could move the boil pot inside and transfer, there, but that would be difficult, given as it's still connected to the recirculation pump. What's happening here, folks? Has anyone dealt with anything similar? If so, how did you fix it?

Are you noticing issues with your finished product or just in the separate sample you put off to the side? How long does it take to cool your wort to pitching temp?

I suspect it's virtually impossible to keep all unwanted microscopic critters out of your wort, unless you're brewing in a clean room. However, if you pitch the right amount of yeast into well aerated wort (something you don't mention in your step by step list), then the yeast should out compete those other nasties and your beer will be fine.

 

[ColoHox]

The sample is kept in a warm (70-75F) cabinet, and typically begins to show signs of spontaneous infection anywhere between 36 and 48 hours. Only once did the sample show no signs of infection for a full week.

The infection starts as a thin foam ring around the edge of the glass, followed by what looks like a thin kreusen, with bubbles and what look like yeast rafts. If allowed to go for a full week, the wort becomes cloudy.

The sample smells ... dank. Dirty and earthy, almost like spoiled vegetables. When poured out, the wort isn't thick and ropey, so this isn't pedio, I don't think.

Your first two paragraphs describe the beginnings of a normal fermentation, including cloudy wort. The smell on the other hand is concerning. You also haven't mentioned the taste! Please tell me you have tasted it before pouring batches out.

 

[broadbill]

OK...so as I read it you think you have a problem with infections because you leave out a wort sample that has not had brewing yeast pitched into it, and it develops an infection in time.

Well, duh....of course it will eventually develop an infection if it is not prepared and kept in a sterile environment! This will happen with any sort of nutritive environment/solution/mixture/etc!

Did this hair-brained idea come from one of Chris White's and Jamil Zenasheff's books? I recently read/commented on a post that mentioned this very same "experiment" from these guys' book....I respected both to of them, but I have to say this is a stupid idea if I ever heard one. It is a problem in search of a solution.

If your actual beer wort you pitch good yeast into doesn't develop an infection, why worry what happens to a unpitched sample? At best, it gives you minimal info about your process, at worst it makes you worry about a problem that you don't have.

 

[ColoHox]

OK...so as I read it you think you have a problem with infections because you leave out a wort sample that has not had brewing yeast pitched into it, and it develops an infection in time.

Well, duh....of course it will eventually develop an infection if it is not prepared and kept in a sterile environment! This will happen with any sort of nutritive environment/solution/mixture/etc!

Did this hair-brained idea come from one of Chris White's and Jamil Zenasheff's books? I recently read/commented on a post that mentioned this very same "experiment" from these guys' book....I respected both to of them, but I have to say this is a stupid idea if I ever heard one. It is a problem in search of a solution.

If your actual beer wort you pitch good yeast into doesn't develop an infection, why worry what happens to a unpitched sample? At best, it gives you minimal info about your process, at worst it makes you worry about a problem that you don't have.

Oh man, missed that. OP, you are complaining you have a problem with infection because a hydrometer sample without yeast grew some gunk? What is your fermenter full of beer like? Any infection there?

+1 to broadbill

 

[jcp]

Oh man, missed that. OP, you are complaining you have a problem with infection because a hydrometer sample without yeast grew some gunk? What is your fermenter full of beer like? Any infection there?

Hey, guys. Thanks for the replies, so far. I am, in fact, getting that same "dank, earthy, dirty" taste in some of my beers. It typically takes a couple of weeks in the bottle to develop.

Don't get me wrong -- it's subtle, but persistent. I dumped some old brews I had, kicking around: an amarillo blonde, a NZ pale ale, and a peach wheat. All of them had that earthy smell and taste.

Yes, I know that many professional breweries fail the "George Fix" test; that's not what I'm trying to do, here. I'm just trying to isolate where in my process that taste and smell is coming from, and I'm at a loss to say how I could improve it.

 

[B2Barleywine]

I wouldn't rule out oxidation... What is your racking/bottling procedure?

 

[stonebrewer]

Could be your fermenter or chamber has bugs in one or both. Only sure way to kill them is to autoclave them, which is probably not practical. I suggest you get a new carboy (bucket) and try making an ale or something that does not require temp control and see if you are still getting an infection. I have a friend who got an infection from his aeration wand as he forgot to clean and sanitize it. Others I know have had issues with tubing and spigots. I have three piece spigots and take them apart after each brew. There is always a half spoon of wort trapped inside them!

Have you looked at your hops as the source of the earthy, dank flavor? Many hops give me this, especially home grown hops for some reason. Hops like Columbus which I use a LOT of give an earthy character. I get this with other hops as well, like EKG or Fuggles (forget which one).

 

[jcp]

Have you looked at your hops as the source of the earthy, dank flavor? Many hops give me this, especially home grown hops for some reason. Hops like Columbus which I use a LOT of give an earthy character. I get this with other hops as well, like EKG or Fuggles (forget which one).

You know, this is the sort of "outside of the box" thinking that I could use! The ones that had the earthiest, dankest character have been with unusual hops.

The NZ Pale Ale used Moteuka and Nelson Sauvin. That was by far the dirtiest.

Another was Ahtanum and Columbus. I did recognize the Ahtanum as being a hop flavor that I didn't like, but there was that earthiness there, too. Columbus?

I wonder if the fermentation in the sample (which, as others have pointed out, is almost certain to happen in everything but a clean-room environment) and the earthy dankness in the beer are unrelated? That would make me feel good about my process.

It would also make me feel silly about not knowing my ingredients well enough. Maybe I should trawl the Recipe/Ingredients forum for threads about "bright and clean" hops, versus "dank".

Thanks, again, for the feedback folks.

 

[IsaacmanTX]

Take a small amount of the suspect hops and make a tea out of them and see if the flavor is indeed from them... Might answer your questions.

 

[Ohbsolutely]

You mention a pump, yes? I also have been currently dealing with a few bad batches - first time ever - and it has had me just as frustrated. My thought was that I recently started to use a pump to recirculate during the chilling process. I start 15 min before the end of the boil. Kettle - Pump - Plate Chiller - Back to kettle. I know many people use this process, but I have stopped for the time being to see if that is what my issue is. Me thinks yes at this point.

Just a thought to consider.

 

[Ohbsolutely]

Could be your fermenter or chamber has bugs in one or both.

Could you elaborate about potential bugs in the chamber? I use a freezer and - while i certainly keep the thing clean - I have thought because the carboys are protected from air getting in, I need not be as paranoid?