Baking Powder

Baking powder is used as a leavening agent for a range of doughs and batters for items such as cakes, puddings, scones and biscuits. It is made from a combination of alkaline and acid substances (usually bicarbonate of soda and cream of tartar) that react when they come into contact with moisture and warmth to produce carbon dioxide bubbles. These bubbles expand during the cooking process to cause the baked item to rise, producing a fine, delicate-textured result.

In the UK, baking powder is usually single-acting; that is, it reacts as soon as it comes into contact with liquid. This means that it is important to work quickly once the milk or water has been added to the dry ingredients so that the resulting carbon dioxide does not have a chance to escape. Double-acting baking soda, which is widely available in North America, is much easier to use as it reacts in two stages: first becoming activated when it is mixed with the liquid and then again when it is exposed to the heat of the oven.

Baking powder must be kept in a cool dry area - any hint of moisture will set the chemicals working. You can make your own by mixing half the quantity of bicarbonate of soda to cream of tartar. If sour milk is in the mixture, equal quantities should be used instead.

      Bicarbonate of Soda