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
Bost's Bread "The Best Taste You Ever Toasted", and "Baked Slow to Sell Fast" became bywords and embedded into the cultural slang-speak of the area where Bost's Bread was sold. In the late 1970s the Bost's Bakery was sold to Wonder Bread, which operated the Bakery for a decade, adding its staple "Wonder Bread", Twinkies, frosted cupcakes and other confections to the product line alongside the bread products. In the late 1980s the parent company of Bost's and Wonder Bread shut down the bakery, ending a tasty chapter in the history of Shelby and Cleveland County, North Carolina. Wonder Bread and Hostess