Ever curious about the microbial universe, I began to look for scientifically backed research to demonstrate the antiviral properties of fermented foods. The different studies I found vary in factors such as which viral organisms are tested, what the food source is, and which yeasts or bacteria are being used in testing. But it paints a promising picture.
Fermentation of foods creates a low pH (high acidity) environment, which is generally hostile towards pathogenic microbes such as viruses.
The studies show that:
- Bacteria create metabolic by-products such as bacteriocins, some of which are used to fight pathogenic microbes. Source
- Lactobacillus plantarum, one of the common probiotic bacterial species, and other bioactive compounds found in kimchi ingredients have been found to hinder the growth of influenza virus. Source
- Viruses such as murine norovirus (affecting mice) and feline calicivirus (affecting cats) were inhibited significantly by acidic pH produced by lactic acid, and also by the substances alliin (found in garlic) and capsaicin (found in red pepper), common ingredients in kimchi. Source
- Probiotic and other lactic acid bacteria secrete antiviral substances during their growth, as the infectivity of the [VSV] virus was diminished by 68%. Source
- Viruses have been well proved to be inactivated by Lactobacillus bacteria and yeasts such as Saccharomyces in fermented edible waste material (i.e. human food waste that is turned into animal feed) due to the low pH, temperature, or fermentation by-products. Source