Should botulism bacteria be a concern making fermented hot sauce? - Ask Extension
I am fermenting peppers from my garden for hot sauce. I understand the bacteria that produces botulinum toxin can grow in anaerobic environments. If...
Knowledgebase
Should botulism bacteria be a concern making fermented hot sauce? #815501
Asked October 29, 2022, 2:59 PM EDT
I am fermenting peppers from my garden for hot sauce. I understand the bacteria that produces botulinum toxin can grow in anaerobic environments. If my peppers are submerged in brine, do I need to worry about botulism growth?
Washington County Oregon
Expert Response
Great question!
We are always concerned about the potential for our food preservation and storage methods to create unsafe situations, particularly related to botulism. Clostridium botulinum can form a deadly toxin under very specific conditions (anaerobic conditions, pH >4.6, temperatures above refrigeration, and high water activity). Most vegetable fermentations create these conditions and yet we rarely have problems with botulism in these foods - which is curious. (We do see botulism cases in fermented fish, but these are quite different from vegetables fermentations). We don't know the exact reasons why vegetable fermentations tend to be safe, but I believe it is a combination of things that reduce the risk: 1) We add salt to give the fermentative organisms ("the good guys") a competitive advantage. (The salt addition isn't enough to prevent C. bot from growing, but it lets the good guys work faster and produce acid to get the pH down.), 2) We don't heat treat the vegetables before we start the fermentation. Heat treatment tends to activate bacterial spores (like C. bot) and trigger them into growing. Since we don't heat treat, we aren't triggering them, so they are less likely to germinate and produce toxin. Neither of these are perfect controls for botulism, but the combination seems to work. I wish I could give you a stronger answer with a lot of scientific evidence behind it, but there has not been a lot of research to determine the exact conditions that will control C. bot in fermented foods.
Ideally (for food safety purposes), a food fermentation would get the pH of the system below 4.6 as fast as possible. Use trusted sources for fermentation recipes and pay special attention to the ratios of products and salt.
I hope this helps. Thanks for using Ask Extension!
Joy
We are always concerned about the potential for our food preservation and storage methods to create unsafe situations, particularly related to botulism. Clostridium botulinum can form a deadly toxin under very specific conditions (anaerobic conditions, pH >4.6, temperatures above refrigeration, and high water activity). Most vegetable fermentations create these conditions and yet we rarely have problems with botulism in these foods - which is curious. (We do see botulism cases in fermented fish, but these are quite different from vegetables fermentations). We don't know the exact reasons why vegetable fermentations tend to be safe, but I believe it is a combination of things that reduce the risk: 1) We add salt to give the fermentative organisms ("the good guys") a competitive advantage. (The salt addition isn't enough to prevent C. bot from growing, but it lets the good guys work faster and produce acid to get the pH down.), 2) We don't heat treat the vegetables before we start the fermentation. Heat treatment tends to activate bacterial spores (like C. bot) and trigger them into growing. Since we don't heat treat, we aren't triggering them, so they are less likely to germinate and produce toxin. Neither of these are perfect controls for botulism, but the combination seems to work. I wish I could give you a stronger answer with a lot of scientific evidence behind it, but there has not been a lot of research to determine the exact conditions that will control C. bot in fermented foods.
Ideally (for food safety purposes), a food fermentation would get the pH of the system below 4.6 as fast as possible. Use trusted sources for fermentation recipes and pay special attention to the ratios of products and salt.
I hope this helps. Thanks for using Ask Extension!
Joy
