The baking process does not require any fat to be used to cook in an oven. When baking, consideration must be given to the amount of fat that is contained in the food item. Higher levels of fat such as margarine, butter, lard, or vegetable shortening will cause an item to spread out during the baking process.
With the passage of time, breads harden and become stale. This is not due to moisture being lost from the baked products, but more a reorganization of the way in which the water and starch are associated over time. This process is similar to recrystallization and is promoted by storage at cool temperatures, such as in a domestic refrigerator or freezer.
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