Ballpark Yellow Mustard Recipe
In a high-speed blender, combine the water, mustard, sauerkraut juice, lemon juice, honey, turmeric, sea salt and garlic. Blend on high speed until smooth, about 30 to 40 seconds. Scoop the mustard into a 1-pint mason jar with a lid, leaving at least 3/4 inches of empty space at the top of the jar. Seal and store at room temperature for 3 days. After fermentation, fully stir the vinegar into the jar and refrigerate. Because vinegar slows the fermentation process, it is added after the 3-day ferment.
From Back to Butter: A Traditional Foods Cookbook (Fair Winds Press) by Molly Chester and Sandy Schrecengost.