Quick bread leavening agents include a weak base, such as baking soda (sodium bicarbonate) plus a weak acid, such as cream of tartar, lemon juice, or cultured buttermilk, to create an acid–base reaction that releases carbon dioxide. (Quick bread leavened specifically with baking soda is often called "soda bread".) Baking powder contains both an acid and a base in dry powdered form, and simply needs a liquid medium in which to react. Other alternative leavening agents are egg whites mechanically beaten to form stiff peaks, as in the case of many waffle recipes, or steam, in the case of cream puffs. Nevertheless,
A Matter of Loaf and Death began in January 2008; creator Nick Park commented that the production period for the short was significantly quicker than that of the feature-length films "Chicken Run" and "", which each took five years to complete. "A Matter of Loaf and Death" was the first Aardman film to be made using the software Stop Motion Pro. Five models were created for Gromit alone, with scenes being shot simultaneously on thirteen sets. Commenting on the fact that the short would be made directly for a British audience, Nick Park said: "I don't feel like I'm making a film for a kid in