Soda bread pastry flour (made from soft wheat), which has lower levels of gluten than a bread flour. In some recipes, the buttermilk is replaced by live yogurt or even stout. Because the leavening action starts immediately (compared to the time taken for yeast bread to rise), bakers recommend the minimum amount of mixing of the ingredients before baking; the dough should not be kneaded. Various forms of soda bread are popular throughout Ireland. Soda breads are made using wholemeal, white flour, or both. In Ulster, the wholemeal variety is usually known as "wheaten bread" and is normally sweetened, while the term
Baking powder present, some of the baking powder should be replaced with baking soda. For example, one cup of flour, one egg, and one cup of buttermilk requires only ½ teaspoon of baking powder—the remaining leavening is caused by buttermilk acids reacting with ¼ teaspoon of baking soda. However, with baking powders that contain sodium acid pyrophosphate, excess alkaline substances can sometimes deprotonate the acid in two steps instead of the one that normally occurs, resulting in an offensive bitter taste to baked goods. Calcium compounds and aluminium compounds do not have that problem, though, since calcium compounds that deprotonate twice are