A leavening agent is something used to lighten dough or batter. Leavening agents create air, steam, or carbon dioxide gas in the mixture. These substances cause the dough or batter to rise. Leavening agents give cakes and other foods their light, fluffy texture. Probably the most well-known leavening agents are baking powder and yeast. However, baking soda is also used to leaven. Beaten eggs or egg whites are leavening agents, too.
