The main ingredient in traditional Irish soda bread is flour, particularly all-purpose flour. This type of bread is made with basic components: flour, baking soda, salt, and buttermilk, which acts as a leavening agent. Traditional Irish soda bread is distinct because it does not rely on yeast for rising; instead, the chemical reaction between the baking soda and the acidity in buttermilk creates bubbles that cause the dough to rise. This quick bread is typically rustic in texture and is often served warm with butter. Some variations may include additional ingredients like raisins or caraway seeds, but flour remains the foundational ingredient.