fermenting pH and safety after first week?

Hello,

I'm fermenting a pepper mash (with garlic, ginger, soy sauce, and some spices) in a mason jar with a Pickle Pipe lid. Based on the sodium content of the soy sauce, it's equivalent to a little more than 2% kosher salt by weight.

The jar has been in a dark cabinet for about a week at about 70-80 degrees. I've opened it once or twice to taste it. I just took another taste -- the flavor seemed OK, but when I tested the pH it was around 4.9.

Is tasting/eating the mash dangerous? I'm specifically worried about botulism; I thought the ferment would be more acidic at this point and therefore inhospitable to botulism.

Unfortunately, I don't have an initial reading to compare it to. But I'm a little concerned because this ferment has been less active than my airlock ferments (which I stirred daily and therefore oxygenated).

Thanks!
 
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It's mostly due to the salt at the beginning. This is why 2% is generally accepted as the minimum. I personally shoot for 2.5-3%.

Creating an environment that is inhospitable to botulinum is multifaceted, though. Biggest keys are salt, pH, and temperature, and they all interact as well. For reference, they did a study on botulism in Japanese noodle soup:

"No botulinum toxin would occur in "tsuyu" with 4% salt at pH below 6.5 at 20°C; with 1% salt at pH below 5.0 at 30°C; 2 or 3% salt at pH below 5.5 at 30°C; 4% salt at pH below 6.0 incubated at 30°C, even if contaminated with the spores."

So at 2-3% salt and 86 degrees F (significantly warmer than ideal), they weren't seeing botulinum proliferation at pH almost as high as 5.5.

I'm...
I usually try to get mine down to 4.0 or below. It usually takes at least a couple weeks. A problem you will run into is if you bottle too soon it may begin to ferment again and blow up when you open it. As far as tasting I do but I grab some from under the surface to avoid any contaminants that may be in there. Hope this helps.
 

salsalady

Business Member
Opening the jar is a huge no-no. Once fermentation starts, the CO2 pushes out the oxygen. It needs to be an oxygen free environment for safe fermentation. I wouldn't trust it at this point...
Just my .02~
 
Thanks. I ended up throwing it out. My current ferment is in a vacuum bag, which is much easier to maintain.

Still curious though: fermentation with an airlock – in the first week – is a moist, low-acid, unrefrigerated, anaerobic environment. Especially with a low brine salinity (2%), why isn't botulism a bigger concern?

According to the USDA:
When ideal conditions exist for growth, the spores produce vegetative cells which multiply rapidly and may produce a deadly toxin within 3 to 4 days of growth in an environment consisting of:
  • a moist, low-acid food
  • a temperature between 40° and 120°F
  • less than 2 percent oxygen.

Even if I hadn't opened my fermentation jar, the pH still would have been >4.6 on day 7.

C. botulinum takes 3-4 days to start producing toxin. I've read plenty online about how botulism from fermentation only happens in exceptional cases, but why is that?
 
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Kramer

Extreme Member
It's mostly due to the salt at the beginning. This is why 2% is generally accepted as the minimum. I personally shoot for 2.5-3%.

Creating an environment that is inhospitable to botulinum is multifaceted, though. Biggest keys are salt, pH, and temperature, and they all interact as well. For reference, they did a study on botulism in Japanese noodle soup:

"No botulinum toxin would occur in "tsuyu" with 4% salt at pH below 6.5 at 20°C; with 1% salt at pH below 5.0 at 30°C; 2 or 3% salt at pH below 5.5 at 30°C; 4% salt at pH below 6.0 incubated at 30°C, even if contaminated with the spores."

So at 2-3% salt and 86 degrees F (significantly warmer than ideal), they weren't seeing botulinum proliferation at pH almost as high as 5.5.

I'm not suggesting this as to cut corners, you should always do your homework and be as clean and deliberate as you can. Merely saying there are multiple factors that work in concert to make fermentations safe. Provided you've got enough salt to slow the initial proliferation of botulinum, are shooting for a cooler temperature (I like mid to upper 60's F), and have live lactobacillus actively lowering the pH, this really reduces the window of opportunity for infection to an acceptable range.

Just my .02
 
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