Fresh Horseradish Relish with Apples and Cranberries

In a food processor fitted with the shredding disk, separately shred horseradish root, carrot, beet and apple; transfer to a large bowl. Using the blade of the food processor, pulse cranberries with sugar until finely chopped. Mix the cranberry mixture into the shredded fruit and vegetables along with vinegar; season with salt. Allow to stand in the refrigerator for 3 days or up to 1 week before serving.