Fermented Mustard

You can buy mustard seeds and grind them into powder for different flavors. Black mustard seeds are the most pungent. Brown mustard seeds are used mostly in Europe, and yellow and white are the mildest flavor. To grind them, use a mortar and pestle or a coffee grinder, cleaning it well when you’re done.
Servings: 2 cups



  • Mix all ingredients until well blended, adding more water if necessary.
  • Place in 2 pint size jars and cap tightly, leaving a 1-inch head space at the top of the jar.
  • Let sit at room temperature for 3 days, then transfer to refrigerator


Mustard powder mixed with a liquid will produce a very smooth, but also hot, mustard. Japanese mustard is simply water and mustard blended together and served quickly.The heat of mustard is in the endosperm, the “meat” of the seed, not the hull. To cut the heat, you can mix a small amount of flour into the mustard. A mixture of powder and coarsely ground seeds produces a grainy mustard.
Storage note: This can be kept in a covered airtight jar in the refrigerator for up to three months.