Mold (& other forms of "low life") can grow anywhere! When I was
flying helicopters, we had to put an algicide additive in the fuel
to prevent algae contamination. Citric acid is a lot more attractive
to life than kerosene (JP4).
I found this at:
The discovery of citric acid has been credited to the 8th
century alchemist Jabir Ibn Hayyan (Geber). Medieval scholars in
Europe were aware of the acidic nature of lemon and lime juices;
such knowledge is recorded in the 13th century encyclopedia
Speculum Majus (The Great Mirror), compiled by Vincent of
Beauvais. Citric acid was first isolated in 1784 by the Swedish
chemist Carl Wilhelm Scheele, who crystallized it from lemon
juice. Industrial-scale citric acid production began in 1860,
based on the Italian citrus fruit industry. In 1893, C. Wehmer
discovered that Penicillium mold could produce citric acid from
sugar. However, microbial production of citric acid did not
become industrially important until World War I disrupted Italian
citrus exports. In 1917, the American food chemist James Currie
discovered that certain strains of the mold Aspergillus niger
could be efficient citric acid producers, and Pfizer began
industrial-level production using this technique two years
In this production technique, which is still the major
industrial route to citric acid used today, cultures of
Aspergillus niger are fed on sucrose to produce citric acid.
After the mold is filtered out of the resulting solution, citric
acid is isolated by precipitating it with lime (calcium
hydroxide) to yield calcium citrate salt, from which citric acid
is regenerated by treatment with sulfuric acid. Krebs cycle
Main article: citric acid cycle
Citric acid is one of a series of compounds involved in the
physiological oxidation of fats, proteins, and carbohydrates to
carbon dioxide and water.
This series of chemical reactions is central to nearly all
metabolic reactions, and is the source of two-thirds of the
food-derived energy in higher organisms. It was discovered by the
Sir Hans Adolf Krebs. Krebs received the 1953 Nobel Prize in
Physiology or Medicine for the discovery. The series of reactions
is properly known as the tricarboxylic acid cycle, but it is also
known as the citric acid cycle or the Krebs cycle.
Even acetic acid/kerosene/vinegar can wind up being a great growth
medium for Something! They've all got carbon atoms in the molecules.
Sparex (sodium hydrogen sulfate) and nitric acid (HNO3) are not as
conducive to the growth of most life that we know, which is why you
won't run into this type of problem. (Environmental issues, health
issues are another story...)
I would recommend the next time you need to mix new pickle, first do
1) Empty the crockpot & rinse well (really, really well).
2) Use a dilute solution of bleach to fill the crockpot to the
rim...let the cover soak in a similar solution.
3) Let crockpot & cover soak for at least a half hour.
4) Rinse crockpot & cover (really, really well).
5) Put absolutely fresh acetic acid into the crockpot.
If the crockpot gets contaminated again, then you have the little
beasties growing in crevices you can't clean out. Time for a new
To the chemists out there, please correct me if I'm off the mark!