On food and cooking the science and lore of the kitchen ( PDFDrive ) 569
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dominate and the substances they produce.
Low salt concentrations and temperatures
f a v o rLeuconostoc mesenteroides, which
generates a mild but complex mixture of
acids, alcohol, and aroma compounds; higher
temperatures favorLactobacillus plantarum,
whichproduceslacticacidalmostexclusively.
Manypicklesundergoamicrobialsuccession,
withLeuconostoc dominating early and then
giving way toLactobacillus as the acidity
rises. Some Asian pickles are made not by
spontaneous lactic fermentations, but by the
addition of another fermented “starter”
material, the by-products of producing wine
or miso or soy sauce. Japanesenukazuke are
unique in employing rice bran, whose
abundant B vitamins end up enriching the
pickleddaikonandothervegetables.
Problems
Problems
in
vegetable
fermentations are generally caused by
inadequateorexcessivesaltconcentrationsor
temperatures, or exposure to the air, all
conditions that favor the growth of
undesirable microbes. In particular, if the
vegetables are not weighted down to keep
them below the brine surface, or if the brine
surfaceisitselfnottightlycovered,afilmof
yeasts, molds, and air-requiring bacteria will
form,lowerthebrineaciditybyconsumingits
lactic acid, and encourage the growth of
spoilage microbes. The results may include
discoloration, softening, and rotten smells
fromthebreakdownoffatsandproteins.Even
the helpfulLactobacillus plantarum can
generate an undesirably harsh acidity if the
fermentationistoovigorousorprolonged.
Unfermented, Directly Acidified Pickles
There are also a host of fruit and vegetable
productsthatarepicklednotbyfermentation,
butbythedirectadditionofacidintheform
ofwineorvinegar,whichinhibitsthegrowth
of spoilage microbes. This ancient technique
