THE DIFFERENCE BETWEEN BAKING POWDER AND BICARBONATE OF SODA: IT’S A QUESTION WORTH RAISING!

Baking powder and bicarbonate of soda - forget these magic ingredients at your peril.

They may only be required by the teaspoonful, but these small additions pack a mighty punch when it comes to your sponge.

Miss out your raising agent and your cake will be dense, stodgy and lacking in lightness.

The trouble with raising agents (also called leavening agents) is that they all look virtually the same but work in different ways. Use the wrong one in the wrong quantities and you may find yourself with overflowing cake batters or cupcakes that fall flat.

To get to grips the two main raising agents, here’s a brief guide to their properties:  

Bicarbonate of soda (sometimes called baking soda)

Known to those in white coats as ‘sodium bicarbonate’ and sometimes shortened down to ‘bicarb’, this fine powder is capable of giving sponges that extra oomph.

It is also an ingredient in baking powder (a little confusing, but all will be explained!). Something liquid and acidic needs to be added to this alkali agent before it gets to work releasing bubble after bubble of carbon dioxide to help raise your sponge.

Kick starting this process in the kitchen requires the addition of an acidic ingredient such as lemon juice or, in the case of our famous Red Velvet Cupcakes, vinegar and buttermilk.

An interesting aside is that, once in the oven, bicarbonate of soda can cause cakes to go golden brown on top and can speed up the browning process.

One thing to watch out for when baking with bicarbonate of soda is that it can leave a slightly tangy aftertaste if too much is used, so be sparing and don’t go overboard when measuring out.  

Baking powder

Developed as an alternative to yeast, baking powder is now a staple for bakers and features in countless cake recipes.

It is created when bicarbonate of soda and cream of tartar, an acidic by-product of the winemaking process, are combined with a filler such as rice flour. The alkali bicarb and the acidic cream of tartar react with moisture (such as milk) to create bubbles of carbon dioxide.

The key difference between baking powder and bicarbonate of soda, in practical baking terms, is that it doesn’t require an additional acidic ingredient i.e. it only needs moisture to start releasing air into the mixture.

Baking powder also has a neutral taste, so it won’t disturb the balance of flavour in more delicate mixtures.  

Top tips:

Self-raising flour is plain flour with baking powder added to it. If you’re short of self-raising flour for a recipe you can make your own. Just add half a teaspoon of baking powder per 100g of plain flour.

We specify the use of raising agents with plain flour in many of our recipes. This is so we can tailor the amounts needed of each component rather than relying on pre-mixed self-raising flour.

For this reason, we don’t recommend our bakers substitute plain flour for self-raising flour or vice versa.

With all raising agents, be sure to give them a good sifting to remove any lumps that have formed while sat in the cupboard. Once combined with the wet ingredients, your raising agents will start fizzing away to make lots of air bubbles.

To ensure you don’t lose this air, get your mixture into the oven as soon as possible or the protein structure that locks air bubbles into the sponge will start to collapse.

Take note of their use-by date as old raising agents lose their effectiveness.