How to Make Fermented Ketchup

If you’re looking for an easy way to introduce fermented and probiotic foods to your family, fermented ketchup is one of the best ways to start. Kids and ketchup naturally go together, and it’s a no-fuss way to swap out processed foods full of corn syrup with a healthier alternative.

Fermented ketchup is easy to make—you can make it in less than an hour—but it doesn’t taste like store-bought ketchup. Although the texture is a close relative, the flavors are deeper, and each bite is slightly different.

Fermented ketchup is heartier, with a thicker texture.

Once you start eating it, you won’t want to go back. You can use it in cooking just like regular ketchup, and it will lend a more layered level of flavor to your meals. You’ll love it!

This condiment differs from other homemade ketchup recipes because you will use a starter culture to begin the fermentation process. In this recipe, I use either whey, which has a flavor mild enough to blend with anything, or fermented vegetable juice, which is a nice complement to the tangy-ness of ketchup.

Although whey and fermented vegetable juice are not the same thing, they both serve the same purpose of introducing beneficial bacteria into your condiment to allow the beneficial bacteria to grow.

Some recipes recommend kefir, but I don’t think it is a good idea to use milk kefir. Milk kefir is tasty, but it’s a thickened form of milk. When the milk has turned into kefir, it resembles fizzy sour cream, and I don’t think you’ll be happy with the results. There are better options.

A word about salt. For this recipe, I recommend Himalayan salt which is full of wonderful minerals. Steer away from iodized salt because it will throw off your beneficial bacteria and it doesn’t have the same nutritional value.

Similarly, I recommend organic honey. Regular honey from the grocery store is frequently sourced internationally, usually from China, and not only has had all the pollen removed from it, but is likely little more than glorified corn syrup. To get the full benefit of honey and bee pollen, stick with organic.

How to Make Fermented Ketchup

A Probiotic Fermented Ketchup Recipe

This recipe makes about a pint of ketchup. It’s easily doubled.


  • 12 oz tomato paste
  • ¼ cup whey or fermented vegetable juice
  • 1/8 tsp red pepper
  • ¼ tsp black pepper
  • ½ tsp allspice
  • 1 Tb Himalayan salt
  • 2 garlic cloves minced & juices released
  • 1 Tb organic honey


I prefer to mix directly in a mason jar. In a pint-sized mason jar, mix the tomato paste, honey, and garlic cloves until thoroughly combined.

Whisk in the whey or fermented vegetable juice, Himalayan salt, allspice, red pepper, black pepper until all ingredients are evenly mixed and the ketchup is smooth.

At this point, you’ve made ketchup.

Now on to fermenting! To ferment your homemade ketchup, use your airlock and lid to seal the mason jar. Let sit in a warm area, out of sunlight, for two to three days, or until it’s fermented to your taste.

Your fermented ketchup will keep in the fridge for months—but I doubt it will last that long because it’s so tasty! Slap it on some French fries, use it as a topping on your next burger, and you’re good to go!


Maat van Uitert is a professional writer and homesteader based in the South. Maat is a fermenting nut who specializes in making cheeses, yogurts, probiotic sauces and condiments to spice up and create flavorful meals. You can read more about Maat and her homestead at FrugalChicken, where Maat helps everyday people achieve independence by raising chickens, learning traditional skills, and becoming more self-sufficient. You can also catch up with her on her weekly podcast, What The Cluck?!, available on iTunes now.

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