Fermentation as Preservation

Before refrigeration, fermentation was humanity's most reliable preservation method. Sauerkraut kept sailors alive on long voyages because lactic acid fermentation preserved cabbage along with its vitamin C, which prevented scurvy.

Korean kimchi follows the same principle — salting vegetables triggers lactic acid fermentation that drops the pH below 4.0, where most harmful bacteria cannot survive.

The chemistry is elegant: beneficial Lactobacillus bacteria thrive in salty, oxygen-free conditions and produce lactic acid. That acid slowly makes the environment too sour for competing organisms, so the good bacteria end up protecting your food.