Leavening is increasing the area of a dough or batter by creating or occluding in them small bubbles of gas, mainly carbon dioxide – produced by yeasts or chemical agents, air or water vapor. It aerates the mixture and thereby lightens it.
These gasses must be retained in the product until the structure is set enough – by coagulation of gluten and egg proteins and the gelatinization of starches, to hold it shape.
Water can acts as a leavening agent in food preparation. When batters and dough are exposed to heat the water present is converted to steam. The steam expands and is responsible for the leavening effect.
For bicarbonate, it produces carbon dioxide in the presence of heat and moisture. Sodium bicarbonate NaHCO3 is the most commonly used product, but ammonium bicarbonate, NH4HCO3 and potassium bicarbonate KHCO3 are used as well.
The type of food is the primary determinant of what type of leavening agent will be used, yeast breads are usually leavened with biological agents such as yeast.
In the labeling, ingredients that act as leavening agents in food may be declared in the ingredient statement by stating the specific common or usual name of each individual leavening agent in parenthesis following the collective name “leavening”.
Function of leavening agents food
