21. An alternative or supplement to leavening agents is a mechanical action by which air is incorporated. 22. No bread, or anything that includes a leavening agent , and most grains and legumes are forbidden. 23. It can hydrate proteins, starch, and leavening agents . 24. Pre-packaged Beer Bread mixes may also be purchased with the dry ingredients and leavening agents already included. 25. :Baking powder is a leavening agent ; that article lists several alternatives, including mechanical ( whisking ) leavening. 26. During Passover, any leavening agents are forbidden. 27. Traditional springerle recipes use hartshorn salt ( ammonium carbonate, or baker's ammonia ) as a leavening agent . 28. The carbon dioxide in the seltzer will act as a leavening agent , producing light and fluffy pancakes. 29. The flour used in parkin in England is self-raising, containing a small amount of chemical leavening agent . 30. This recipes leaves out the leavening agents , which prevents the cookies from rising and spreading during baking.