Acetobacter

[digdoug713]

So I recently had a lid crack and did not notice for about 24 hours. My mead now has a bit of oxidation and vinegar going on. I plan to fractional freeze, if I freeze low enough to freeze the acetic acid can I get enough of the vinegar out or will the acetobacter keep popping back up? Also it seems to be taking much more filtration to remove my carbon than normal.

 

[VikeMan]

I wouldn't count on freezing to kill any bacteria. But if you succeed in removing the existing acetic acid (I have no idea if that's even practical), and you keep the mead cold enough, you might be able to slow the bugs enough that they won't do further damage. That said, it sounds like your original fermentation isn't finished, so if you warm it up to finish, any bugs would take off again.

Also, I wouldn't assume that the culprit is Acetobacter. Brettanomyces or some Lactobacillus species are also possibilities, because they can also make acetic acid in the presence of oxygen. Even Saccharomyces (i.e. regular beer/wine/mead yeast) make acetic acid. Every beer/wine/mead has some acetic acid, but it usually below taste thresholds.

 

[VikeMan]

Also it seems to be taking much more filtration to remove my carbon than normal.

What carbon?

 

[IslandLizard]

Here's some good information on freeze distilling Acetic acid in a mixture that contains water:
https://chemistry.stackexchange.com/questions/2506/acetic-acid-freezing-distilation
I don't see that working for a such a small amount of Acetic acid in a "watery solution."

 

[digdoug713]

Here's some good information on freeze distilling Acetic acid in a mixture that contains water:
https://chemistry.stackexchange.com/questions/2506/acetic-acid-freezing-distilation
I don't see that working for a such a small amount of Acetic acid in a "watery solution."

Dry ice... Just gotta get it colder.

 

[digdoug713]

What carbon?

Was sold with the yeast, first time using carbon. Supposed to help clear it up, seems to be filtering out well. Just taking lots of passes through progressively tighter filters.

 

[digdoug713]

I wouldn't count on freezing to kill any bacteria. But if you succeed in removing the existing acetic acid (I have no idea if that's even practical), and you keep the mead cold enough, you might be able to slow the bugs enough that they won't do further damage. That said, it sounds like your original fermentation isn't finished, so if you warm it up to finish, any bugs would take off again.

Also, I wouldn't assume that the culprit is Acetobacter. Brettanomyces or some Lactobacillus species are also possibilities, because they can also make acetic acid in the presence of oxygen. Even Saccharomyces (i.e. regular beer/wine/mead yeast) make acetic acid. Every beer/wine/mead has some acetic acid, but it usually below taste thresholds.

Will report back with how finished product is. Definitely bellow taste threshold as is, but the smell is noticeable.

 

[MaxStout]

Perhaps your carbon filtration was the source of the infection? Could be a good place for bugs to hide out, unless the carbon was sold to you, sealed and sterile and you kept it sanitary.

 

[digdoug713]

Perhaps your carbon filtration was the source of the infection? Could be a good place for bugs to hide out, unless the carbon was sold to you, sealed and sterile and you kept it sanitary.

Was sold completely sealed and tested by submerging packet in water and squeezing before opening, not sure of its sterility or purity though. Seems like a weird source, but would make sense as it took 24 hours from adding the carbon to noticeable vinegar scent.

 

[MaxStout]

For clarifying, there are fining agents that will do the job. Sparkalloid is one that comes to mind. Something to consider for the next batch.

 

[digdoug713]

For clarifying, there are fining agents that will do the job. Sparkalloid is one that comes to mind. Something to consider for the next batch.

Can you provide more info about how it does this? I am rather doubtful a fining agent will remove vinegar from alcohol. And even more doubtful it will remove physical pieces of carbon. And I am leary of adding more chemicals to this as I didn't notice any vinegar smell until after I added a two part fining agent. Added as per instructions and 24hrs later vinegar scent.

 

[MaxStout]

The fining agent won't help your present mead. It won't remove vinegar, nor will it remove the carbon.

I suggested it for next time, to use instead of carbon for removing particulates in suspension. Fining agents capture floating particulates and settle them to the bottom of the vessel. Then you rack the clarified mead off the lees as you normally would.

 

[digdoug713]

The fining agent won't help your present mead. It won't remove vinegar, nor will it remove the carbon.

I suggested it for next time, to use instead of carbon for removing particulates in suspension. Fining agents capture floating particulates and settle them to the bottom of the vessel. Then you rack the clarified mead off the lees as you normally would.

That's exactly what I did. As stated the only reason for the charcoal was it was included with a yeast I'd never tried before. Usually in my experience, if you're trying something new use all steps and ingredients as directed. And I used a fining agent, not sure what you're suggesting it for as it does nothing to help with either current problem. But either way I appreciate the advice.

 

[digdoug713]

That's exactly what I did. As stated the only reason for the charcoal was it was included with a yeast I'd never tried before. Usually in my experience, if you're trying something new use all steps and ingredients as directed. And I used a fining agent, not sure what you're suggesting it for as it does nothing to help with either current problem. But either way I appreciate the advice.

The fining agent won't help your present mead. It won't remove vinegar, nor will it remove the carbon.

I suggested it for next time, to use instead of carbon for removing particulates in suspension. Fining agents capture floating particulates and settle them to the bottom of the vessel. Then you rack the clarified mead off the lees as you normally would.

Also, as per the yeast instructions carbon goes in with your initial fill up and is just supposed to help keep contamination down during fermenting and from what I can tell doing research maybe help remove bitterness. Seems the science of the carbon is far less about clearing or they wouldn't provide yeast, carbon, and a two part fining agent.

 

[digdoug713]

Perhaps your carbon filtration was the source of the infection? Could be a good place for bugs to hide out, unless the carbon was sold to you, sealed and sterile and you kept it sanitary.

Was sealed, and I kept it completely sterile even using gloves and clean glass utensils. But as to the condition before it was packaged no clue. I'm still leaning towards air contamination, as I said previously there is a visible crack in my lid I did not notice and carbon went in day one. In my mind it's definitely down to air or the two part fining agent. No smell, then follow fining instructions, 24hrs later smell.