While most fermented foods are safe, it's still possible for them to get contaminated with bacteria that can cause illness. In 2012, there was an outbreak of 89 cases of Salmonella in the US because of unpasteurised tempeh.

What are the risks of fermentation?

The most common reaction to fermented foods is a temporary increase in gas and bloating. This is the result of excess gas being produced after probiotics kill harmful gut bacteria and fungi. Probiotics secrete antimicrobial peptides that kill harmful pathogenic organisms like Salmonella and E. Coli.

Can fermented food be toxic?

Fermented foods (FF) are widely consumed around the world, and FF are one of the prime sources of toxins and pathogenic microbes that are associated with several foodborne outbreaks. ... Fermented milk products and meat sausages are extremely vulnerable to contamination.