Baking Soda, Bicarbonate of Soda and Baking Powder are raising (leavening) agents which are added to your recipes to assist with the ‘rising’ process of your baked goods.
Baking Soda or Bicarbonate of Soda as it’s known in the UK is the pure form of sodium bicarbonate, and when combined with an acid, it produces bubbles of carbon dioxide. (If you have ever added bicarbonate of soda and white vinegar to clean your sink/drains then you’ll know about the bubbles and fizz I’m talking about).
If you add bicarbonate of soda to any ‘acid’ ingredient such as lemon juice, buttermilk, yoghurt etc. in your cake batter and then infuse heat from your oven, this will create a chemical reaction which allows your baking to rise.
Tip: Anything that contains Baking Soda or Bicarbonate of Soda MUST be baked immediately; otherwise, it will fail to react and fall flat.
Also adding too much baking soda to your ‘acid’ ingredient can cause an imbalance and leave you with residual baking soda in the baked goods, this, in turn, could leave a rather unpleasant taste to your baked goods. Just remember less is more!
Baking Powder, on the other hand, does actually contain Baking soda, it also contains Cream of tartar and Cornflour, the Cream of Tartar is the acid, and the Cornflour is a drying agent.
This double-acting powder reacts in two phases the first being when the baking powder gets mixed in with your wet ingredients the first reaction occurs as a little gas is created and then phase two is when the batter is placed in the oven. The ingredients reacts with the heat and allows further gases to escape.
Baking powder can be found in recipes for cookies, cakes, puddings and scones.
Tip: Always read the label concerning your baking powder as there are two types the single-acting powder which if included in your recipe has to be baked immediately or the double-acting powder as above which can be added to your mixture in advance and left to sit for a while. Most stores generally sell the double-acting powder but always remember to check.