Spiral Foods Plum Vinegar- A condiment rich in organic acids, Ume-su is a by-product resulting from the manufacture of Umeboshi (salted plums). It has a unique sour/salty taste. Sprinkle over cooked or steamed vegetables, add to salad dressings and dips, and use for pickling. 4.3 percent acidity. Fat free, Gluten free and high in antioxidants