Cultured Catsup - or - Fermented Ketchup
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Homemade ketchup is so good, but fermented is even better!
  • 2 litres/kg tomatoes, pureed (2 canning jars)
  • 100g (roughly ¼ - ⅓ cup) honey
  • 100g (roughly ¼ - ⅓ cup) maple syrup
  • 1 ½ cups raw cider vinegar
  • ½ cup whey
  • 1 small onion, finely diced
  • 1+ tsp. garlic powder
  • 1+ tsp. mustard powder
  • Salt
  • Other seasonings you think would taste good…
  1. Cook the canned tomatoes for a long time over low heat, stirring a few times every hour. You can use a slow-cooker, I just used a Dutch oven over very low heat. Let them cook for 4-8 hours, however long it takes to get them thick. If they are not sufficiently uniform puree them in a food processor or with an immersion blender.
  2. While the tomatoes are cooking dice the onion and soak it in the vinegar to infuse it with some oniony goodness.
  3. After the tomatoes have reached your desired thickness cook them a bit more. Then add 1 cup of the onion-infused vinegar along with the honey, maple syrup, garlic, mustard, salt, and cook 15-20 minutes more. Remove from heat and allow to cool.
  4. When the ketchup is cool mix in the rest of the vinegar and the whey. Transfer to a jar, cover loosely and allow to ferment at room temperature for 1 or more days. Then store in the fridge. You can even transfer it to a store-bought ketchup container in hopes of fooling your kids who may have a preference for how ketchup “should” taste….
Recipe by The Local Kitchener at