Stages of Lactic-Acid Fermentation

Here are short notes for Lactic-Acid fermentation. It is very brief but provides enough information for remembering the main stages.

Lactic-Acid fermentation is:

Disclaimer: The information provided here is not intended to be medical or professional advice. Any use of this information is at your own risk. Readers are encouraged to educate themselves in the specific area and should always verify any information before using it.

Stage 1 - Becoming Anaerobic (0 - 2ish days)

In the bottle with 2.5% salt water, vegetables must be submerged. The lid should not be tight because CO2 will be produced and must replace oxygen to kill aerobic pathogens. Alternatively, you can use specialized one-way lids for fermentation.

2.5% salt is calculated as (vegetable_weight + water_weight) * 0.025.

Stage 2 - CO2 and Acidic (2 - 5ish days)

The main actor in stage 2 is Leuconostoc bacteria.

Leuconostoc Bacteria

  • Anaerobic
  • Salt tolerant

Produces Lactic Acid and Acetic Acid, which significantly lower the pH. It also produces CO2, which stimulates probiotics and removes remaining oxygen.

Leuconostoc bacteria are not acid tolerant. When the environment becomes too acidic, they die.


Produces CO2.

Stage 3 - Probiotic and Nutritive Development (±5 days)

During stage 3, Lactobacillus bacteria thrive.

Lactobacillus Bacteria

  • Anaerobic
  • Salt tolerant
  • Acidic tolerant

Produces Lactic Acid. In this stage, Lactobacillus creates nutrients such as GABA, B Vitamins, enzymes, and polyphenols.

When is Fermentation Done

Mature ferment is about 20 - 30 days. The minimum is 14 days. This is just a general recommendation and will differ for specific kinds of fermentation.