Everybody loves a good fermented hot sauce! The question is, do you prefer a mild, medium, or hot sauce? But how to make the best fermented hot sauce? Read on for a recipe and information on how to use a starter culture.

Chilies are vegetables

Chilipeppers are vegetables, just like cabbages or carrots. (Botanically they are actually fruit, but let’s not get into that). So, if we want to ferment chilipeppers, we are dealing with lactic acid fermentation or ‘lacto fermentation’. 

The lactic acid bacteria present in the vegetables are going to convert the sugars into lactic acid. As a result, the ph lowers to a level where spoilage and pathogenic bacteria are eliminated. Most microorganisms thrive best in a neutral pH environment of 7, such as water. Below 4.6, you may argue that your food is bacteriologically safe.  You can easily measure this the pH with pH strips.

Fermented chillies

Did you know? Chili pepers are botanically fruit. Just like cucumbers, okra’s and eggplants. Basicly anything with seeds is a fruit.

3 ways to deal with the lack of sugar in chilies

What’s important to understand is that chilies (which includes habaneros) do not typically offer sufficient levels of sugar for the fermentation to be successful.

There’s a few ways to deal with this:

  1. add other vegetables
  2. add some fruit
  3. use a vegetable fermentation starter culture

The advantages of using a starter culture for fermenting chillies

Adding a starter culture to your vegetable ferments has a number of advantages:

  • Flavor. It is a great way to pack a bit of extra flavor into your ferment 
  • Consistency and control. Instead of having varying results between batched because of differences in bacteria on your veggies, adding a starter culture will give you consistent results. This can be particularly important if you want to sell your fermented hotsauce
  • Safety. If you add a starter culture you add so many of the good bacteria that the chances of ‘bad’ bacteria growing are are virtually zero.
Fermented hotsauces

Fermented hotsauce recipe


  • 1 kg of chilies, jalapeños, etc.
  • 250 grams of sliced carrots/onions
  • 150 grams of fruit (e.g. banana, mango)
  • a fermentation starter culture (optional)
  • Sea salt
  • Enough water to submerge your vegetables


  1. Use gloves. Really. Good ones!
  2. Slice the chilies into small pieces, and leave the seeds and white ribs if you prefer a real hot sauce.
  3. Always slice peppers in order to ferment them as they are hollow and may contain unwanted bacteria that could contaminate your whole sauce.
  4. Mix in the sliced carrots, onions and fruit.
  5. Mix the vegetable starter with water and leave it to sit for 10 minutes so it activates.
  6. Meanwhile, weigh your fermentation jar
  7. Place your peppers and other ingredients in a clean 5-liter jar bucket
  8. Add as much water as is needed to submerge your veggies.
  9. Add the starter and mix
  10. Weigh the total weight of the ingredients + water and mix in 1,5% sea salt. That means, if you have 1,25 kg of chillies and 500 ml of water, this totals to 1,75 kg. 1,75 * 15 = 26,25 grams of salt
  11. Mix well
  12. Weigh down the vegetables. Make sure that the peppers are completely submerged.
  13. Keep at (ideally) 15 and 18 degrees Celcius and allow to ferment for at least one week. You can taste the peppers at the one-week mark and then at two days intervals until you’ve reached the desired flavor.
  14. Optionally: test your pH. It should be below 4.6
  15. Remove most of the liquid (don’t throw it away) and chop to a fine paste/sauce. Add the liquid until you have the desired consistency.
  16. Bottle and keep in the fridge.