[CH] Re: Fermented Mash Sauce Questions
George Nelson (70431.3065@compuserve.com)
Thu, 7 Jan 1999 23:04:29 -0500
Cameron Begg and Kristofer Blennow have an interesting dialog going on
about salt-promoted acidic fermentation of chiles.
The major question is about molds. While molds are inhibited (or even
killed by low pH), they can live on the surface of an inhospitable
environment (too low a pH or excessive salt). In acid, they do this by
metabolizing the acid and releasing the metabolites in their local area,
diluting or neutralizing it. They may be able to do the same in a salty
medium to dilute it more to their "liking."
This alone is a good reason to prevent mold growth since molds will
eventually use up all the acid, raise the pH and allow toxin-producing
bacteria to grow. Molds also have the nasty habit of producing toxins of
their own. Some of these are antibiotics which are a problem only if you
are a bacterium. Others can be carcinogenic. Still others taste bad.
However, I am loathe to throw things away. I try to look in on
fermentations every couple days so I can pick mold off before it becomes
too well established. If the mold has been on more than 7 to 10 days, and
a thick pad covers more than 80% of the surface, I would say it is pretty
far gone. You could lift off the top two inches of the batch to expose a
fresh surface and hope for the best.
On the subject of yeasts and the organism doing the fermentation with
highly-salted chiles, there are osmophilic yeasts which will function down
inside 80% sucrose solutions. Of course in these they get some nutrient.
I have to defer to an expert to determine whether there are yeasts which
can live at 20% w/v salt solutions.
I have done some pepper mashes and remain skeptical there is an alcoholic
fermentation by yeast, however. I think it is some kind of lactic
bacteria. No hard data, just an informed hunch based on
1. most vegetable fermentations being lactic at least part of the time.
2. Pepper carbohydrate to lactic acid is a direct route to acidity, it's
simpler.
3. The process is entirely anaerobic; a yeast-alcohol fermentation
followed by acetic acid production would require introduction of air.
These become acidic without air introduction.
George Nelson
70431.3065@compuserve.com