[skylsdale]

Alright, I've always had a fine time doing the DIY CO2 with the 2 liter bottles...but for some reason it hasn't been working lately. A couple weeks ago one the bottle stopped producing CO2, so I mixed up another batch. Nothing. I waited a few days. Nothing. I cracked open the bottle and it had a rotten smell to it, along the lines of bad eggs. Thinking it might have been the yeast, I tried a different kind...nothing. Within an hour or two it takes on a very rotten smell.

For the life of me, I can't figure out what's going wrong. I tried mixing up a little CO2 with some sugar in a bowl, and I got that nice yeasty bread smell. I do it in the bottle...it stinks to high heaven.

Any ideas?

 

[SnyperP]

I've always felt that the co2 mixtures smelled bad anyways. LOL

 

[Urkevitz]

Mine stink, but they work. Does the bottle fiz when you shake it a little? Maybe you have a leak somewhere.

 

[Darkblade48]

It might be due to some mould or something that is living off the sugar/water solution that you mixed up.

You may want to try to sterilize the bottle somehow. I don't recommend pouring hot water directly into the 2L bottle though, as the hot water will just cause the atmospheric pressure to crush the bottle quite nicely, rendering it useless

 

[skylsdale]

I didn't even think about the mold possibility. The bottle DID sit down in my basement with the sugar/yeast solution for a couple months between taking down a setup and getting another one started. I'm sure that left a door wide open for some stuff to build up in the bottle and affect all the batches I've made. It's weird, though, because one batch actually worked reasonably after I started using it again...but the last few haven't. Maybe the mold has has been able to increase or something?

 

[SnyperP]

I'd just get a new bottle. It'll cost you 99 cents and you can enjoy your favorite type while you mix up a new batch.

 

[Jdinh04]

When I made a new bottle for mine and poured out the old one, man oh man, it smelt very nasty, I was going to gag at the time.

 

[Bonsai_Swamp]

For brewers fermentation is a lot like the plant/algae issue - if the initial yeast growth is retarded for any reason other organisms (wild yeasts, molds, and bacteria) can take over and outcompete the (tame) yeast. You can get some pretty disgusting mixes as a result. On a moderately bad day you only end up with vinegar. On a really bad day there's things like "ropey" beer - looks like beer, pours like snot, tastes like carbonated, vinegary snot (don't ask - I was curious.

Brewers tend to be neat freaks. Equipment needs to be cleaned thoroughly between uses. Sterilants are available, but many do fine with lots and lots of clean water and thorough scrubbing.

Some plastics are porous enough that the spoilage organisms can remain in the plastic walls of the container and re-infect future batches, which is why some brewers use only glass. Since 2 litre bottles are easy to find and a lot cheaper than 20 litre carboys, I'd recommend a new bottle at the first whiff of anything nasty.

 

[HeyPK]

It sounds like you have some kind of bacteria that has taken over and out-competes the yeast. You should be able to sterilize your bottle, tubes, and everything that the solution might come into contact with with 10% liquid bleach and then start over with a new batch of yeast.