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#1 Howiest

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Posted 19 December 2017 - 07:45 PM

Hey all,

 

So the fermentation thing produces CO2, which being heavier than air pushes the oxygen out of the airlocks, leading to an anaerobic environment in the jar, right? I'll bounce it off my coworker in grad school for biochemistry, but if I were to inject a little CO2 into the jar or vessel after filling, would that help ensure nothing "bad" would grow? I know the pH drops as the fermentation happens, and that helps, but would an initial purge be beneficial?



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#2 The Hot Pepper

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Posted 19 December 2017 - 07:48 PM

 It's where botulism thrives so don't mess around lol.



#3 Howiest

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Posted 19 December 2017 - 08:03 PM

lol, thats why I ask! Botulism  is anaerobic, and I feel silly for not catching that.

 

Not to split hairs, but "air" isn't clearly defined, and as a scientist, I like clarity. It's admittedly picking fly shit out of the pepper, since botulism likes "that" environment, but I think the reference to "air" is dated, and when you think about it, anything with any headspace would be deemed aerobic, regardless of the composition of the gases comprising that space, and that just seems wrong, to me.



#4 tctenten

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Posted 19 December 2017 - 08:06 PM

Hey all,
 
So the fermentation thing produces CO2, which being heavier than air pushes the oxygen out of the airlocks, leading to an anaerobic environment in the jar, right? I'll bounce it off my coworker in grad school for biochemistry, but if I were to inject a little CO2 into the jar or vessel after filling, would that help ensure nothing "bad" would grow? I know the pH drops as the fermentation happens, and that helps, but would an initial purge be beneficial?


This is basically the concept to remove oxygen when bottling beer. I have no idea if it would work on a ferment.

#5 The Hot Pepper

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Posted 19 December 2017 - 08:10 PM

You have to remember the air pockets not just the headspace. That's why infused oils are so dangerous.



#6 The Hot Pepper

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Posted 19 December 2017 - 08:13 PM

PS. An air pocket can be a micro size oxygen molecule inside a garlic mince. I just wouldn't chance it.



#7 tctenten

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Posted 19 December 2017 - 08:13 PM

You have to remember the air pockets not just the headspace. That's why infused oils are so dangerous.


Very true...but if it is still fermenting...they should bubble out. I think it sounds like a great idea to get rid of a good chunk of the oxygen present in the headspace.

But I would definitely bounce this off a scientist.

#8 tctenten

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Posted 19 December 2017 - 08:16 PM

We all ferment without CO2 and have good results, to me this is like added benefit in the process.

#9 Howiest

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Posted 19 December 2017 - 08:17 PM

Fermentations have been done for a long, long time. They work, and I'm not nearly vain enough to suggest I'm going to stumble across the process and make some big improvement. If speeding up the removal of oxygen that can lead to some nasties would just shift things to increase the proliferation of some others, then there is no benefit. I'll definitely bounce this off our resident biochemist and see what she thinks.

 



#10 tctenten

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Posted 19 December 2017 - 08:18 PM

Fermentations have been done for a long, long time. They work, and I'm not nearly vain enough to suggest I'm going to stumble across the process and make some big improvement. If speeding up the removal of oxygen that can lead to some nasties would just shift things to increase the proliferation of some others, then there is no benefit. I'll definitely bounce this off our resident biochemist and see what she thinks.
 


I would love to hear her opinion.

#11 The Hot Pepper

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Posted 19 December 2017 - 08:20 PM

word!



#12 Howiest

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Posted 19 December 2017 - 08:24 PM

We'll science the shit out of this! lol 

 

If I have to pull a vacuum on a test jar or two, we'll give it a go for science sake, and hope like hell the mason jars don't implode :)



#13 tctenten

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Posted 19 December 2017 - 08:27 PM

We'll science the shit out of this! lol 
 
If I have to pull a vacuum on a test jar or two, we'll give it a go for science sake, and hope like hell the mason jars don't implode :)


Should be ok. Most of us vac seal our powders/dried pods in mason jars. Unless you are talking about some supersonic vacuum.

#14 jhc

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Posted 20 December 2017 - 07:48 PM

I dont know that I'd do it. You'd immediately make it a mostly anaerobic environment before the fermentation has a chance to drop the ph into a range where botulism can't grow.

Edited by jhc, 20 December 2017 - 07:48 PM.


#15 Howiest

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Posted 20 December 2017 - 09:01 PM

I dont know that I'd do it. You'd immediately make it a mostly anaerobic environment before the fermentation has a chance to drop the ph into a range where botulism can't grow.

 

Thats a good point, and while the pH issue can be addressed otherwise, I'm certain there are more pieces to the whole puzzle that at least I'm ignorant too.

 

I did mention this whole idea to our biochemist at work, and she launched into a an explanation of the metabolization processes that take place aerobically, and anaerobically, basically, in the presence of oxygen, and without. I'll have to confirm which is was, but one of the two, I'm guessing the anaerobic, requires ~10x as much activity. I'll confirm that since I feel it matters.

 

Any of these organisms, and us humans too, produce/break down adenosine triphosphate (ATP) for fuel. The "good" organisms that do the fermentation, I suspect, might be facultative anaerobes, that can make ATP(cellular fuel) in the presence of oxygen, and can switch to fermentation or anaerobic respiration in the absence of oxygen. (This is probably very important)

 

The "nasties", or at least some of them to include the dreaded botulism, is an obligate anaerobe, which will die in the presence of oxygen(aerobic), but thrive in an environment without oxygen(anaerobic). *This is nothing more than hypothesizing so don't assume ANYTHING from these statements that are most certainly oversimplistic, and probably wrong.

 

Based on the above total butchery of the biochem field, we may hypothesize that the good "bugs" are facultative anaerobes that are able to grow in either environment(aerobic or anaerobic), which allows them to over run and conquer the bad "bugs" that are unable to function in both environments. <---This is a total wild ass scientific guess and probably wrong.

 

If the above is true, it might not be beneficial to purge and create an anaerobic environment too quickly as it COULD allow bad bugs to grow at the same rate as the good.

 

it's way past my bed time, so I'm sure there will be some other input tomorrow.



#16 jhc

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Posted 21 December 2017 - 04:09 PM

Lactobacillus has been described as a faculative anaerobe but I think it's maybe more accurate to call them aerotolerant. They are not poisoned by oxygen like botulism is but they are fundamentally anaerobic bacteria. So pumping in CO2 would make them happy but would make botulism happy too. I don't think it would be a good idea.

#17 Howiest

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Posted 22 December 2017 - 05:21 PM

Lactobacillus has been described as a faculative anaerobe but I think it's maybe more accurate to call them aerotolerant. They are not poisoned by oxygen like botulism is but they are fundamentally anaerobic bacteria. So pumping in CO2 would make them happy but would make botulism happy too. I don't think it would be a good idea.

 

I guess if the lactobacillus can continue growth in the aerobic environment, or even just tolerate it and stay static in regards to growth as you suggest, while the botulism dies, that at least gives the "good" stuff a chance to over run the "bad" stuff before the environment transitions as the fermentation takes place.

 

This whole thing is nothing more than my ignorant pondering, and typing it all out here. Unless I figure out how to quantify the "good bugs" vs the bad, it really doesn't mean much. I have a bunch of stuff on the counter fermenting, my first ever attempt, and I'm not even yet totally comfortable with the process let alone knowledgeable about what is happening. lol, I almost tossed a half full 2.5 gallon jar of habanero/onion/garlic/mandarin orange mash the other day when I saw a pea sized bit of kahm yeast.

 

I'll have to do some looking into the identification and quantification thing.
 



#18 jhc

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Posted 22 December 2017 - 08:43 PM

Seems to me the easiest way to make sure the good bacteria outcompete the nasties is to spike in a bunch of Lactobacillus at the beginning. Probiotic, kimchi juice, sauerkraut juice, whatever.

#19 AlfredW

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Posted 27 December 2017 - 10:27 PM

There are some confusions here about how fermentation works to prevent botulism. Also about the purpose of headspace. 

There are really two stages or conditions for fermented hot sauce. One is the fermentation stage. and the other is how to preserve it post fermentation.

During fermentation one wants to have headspace because the mash will expand and will potentially overflow the container. During fermentation one also needs to have a vaporlock to allow the gasses produced to escape. Fermentation relies on salt to suppress the formation of botulinum then as the lactobacilus grows that also suppresses the botulinum. The lactobacilus also produces acid as a byproduct of growth which also suppresses botulinum.

Once fermentation is complete or nearly complete one can refrigerate the mash. If one wants to make it shelf stable then one needs to kill the lactobacillus. this is done by hot processing. Hot processing will allow one to close the sauce in a container and not have it explode from the further expansion of gasses that would continue because of the live culture contained in it. 

But since the pasteurized sauce will no longer have a live culture in it to crowd out the botulinum (and other baddies) it must be vacuum sealed. This is where headspace becomes important in final canning of Hot processed products. The heated bottle and heated product not only ensures that any live bacterium is killed but it also drives out atmosphere from the container. once it cools there is a vacuum formed from the contracting of air when cooling. This is why when one does hot water bath process and then sets the jars aside to cool one will see and hear when the lids snap at some point in the cooling process. In order for this to work there has to be some headspace. The vacuum created ensures air tight sealing of the product.

At this point it is this combination of proper pasturization which kills the vegetative stage bacterium but not the spores, low ph which suppresses the spores from sprouting the vegetative forms ( lower than 4.6 for any product, better if it is below 4.0, most hot sauce is below 3.5), and an airtight seal to keep out any new baddies.






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