Aiva Baking soda is a white powder with crystalline grains, which is used as a leavening agent. Its main purpose is to break down proteins and neutralize acids. Thus, it aids in leavening and tenderizing. Baking soda is a natural tenderizer. Thus, it can be added to soaked beans, etc. before pressure cooking. Baking soda quickens the cooking process. As a leavening agent, it is used in baking. Baked recipes leavened using baking soda usually have a lighter crumb and show signs of aeration (in form of tiny holes) because of the escape of carbon dioxide.