Bread unpredictable since the steam is not produced until the bread is baked. Steam leavening happens regardless of the raising agents (baking soda, yeast, baking powder, sour dough, beaten egg white) included in the mix. The leavening agent either contains air bubbles or generates carbon dioxide. The heat vaporises the water from the inner surface of the bubbles within the dough. The steam expands and makes the bread rise. This is the main factor in the rising of bread once it has been put in the oven. CO generation, on its own, is too small to account for the rise. Heat
Sandwich bread be prepared using gluten-free flour, teff flour. and other ingredients. In the 1930s in the United States, the term sandwich loaf referred to sliced bread. In contemporary times, U.S. consumers sometimes refer to white bread such as Wonder Bread as sandwich bread and sandwich loaf. Wonder Bread produced and marketed a bread called Wonder Round sandwich bread, which was designed to be used with round-shaped cold cuts and other fillings such as eggs and hamburgers, but it was discontinued due to low consumer demand. American sandwich breads have historically included some fat derived from the use of milk or oil