Soy Protein Powder Soy Protein Powder is a healthy alternative to animal protein as a plant-based dietary source of complete protein. It is easy to digest, has very little flavor and blends smoothly in liquids so you can add it to drinks and other foods for a quick nutritional boost! One serving offers 11mg of soy isoflavones. Add soy protein powder to smoothies, protein shakes, yogurt, hot cereal, soups, granola bars, protein bars, pancakes, muffins, brownies, cakes and breads. Try the delicious drink recipe on the back of the package for starters!