What’s the difference between….
… baking powder, baking soda and bicarbonate of soda.
If you have ever browsed recipes in books or on the internet this may well be a question you have asked yourself. So here goes.
Bicarbonate of soda/baking soda
Bicarbonate of soda is the same thing as baking soda. They are both common names for the compound sodium bicarbonate.
Bicarbonate of soda is an alkali – an alkali is something that is the opposite of an acid. When you cook with it, it reacts with acidic compounds and releases carbon dioxide. This creates bubbles which then causes whatever mixture you are cooking to rise.
Personally I tend to use this round the house as a mild household cleaner. If you take the bicarb (alkali) and some white vinegar (acid), and pour them down a blocked drain with some boiling water, you will see the carbon dioxide do its stuff! It’s a useful tip for clearing a plughole.
It would seem that the term bicarbonate of soda is used in the UK, whereas baking soda is more common in the US.
Cream of tartar
Cream of tartar is a product that forms in wine barrels during fermentation. It comes from tartaric acid, which is something that occurs naturally in grapes.
Its uses, apart from that mentioned below, are to stabilize and give more volume to egg whites, and to produce creamier textured icing and sweets. (That’s frosting and candy for the Americans!)
It is possible to substitute other acids for cream of tartar, such as lemon juice.
Baking powder
Baking powder is something you put in cakes to make them rise. Here in the UK we have two types of flour you would typically use to make cake – plain flour and self-raising flour. As the name implies, self-raising flour makes the cake rise all by itself, but one needs to add baking powder to plain flour.
If you run out of self-raising flour, you can therefore substitute plain flour and baking powder. Most baking powder tubs will tell you how much to add to plain flour on the back of the tub.
But what exactly is baking powder? It’s a mixture of bicarbonate of soda and cream of tartar, together with a filler like cornflour.
And now I think you can see what the point of baking powder is. The alkali and the acid are already present in baking powder. However they do not react until water or moisture is added. So baking powder sits quietly in the tub until needed, and then when mixed with the wet ingredients in a cake, everything is there to produce the carbon dioxide and make those bubbles – and then your cake rises.
Using it is simpler than using bicarbonate of soda on its own because the acid for the reaction to work is already present.
So now you know…
