Self Raising vs Plain Flour: The Differences

Flour is a pretty essential element of most baking recipes. Most flours look, smell and feel the same, so how do you tell the difference? Get it wrong, and your recipes might end up being a gloopy mess, rising too much or not at all! In this article we’ll compare self-raising vs plain flour and highlight the differences between these two essential ingredients!

What technically makes plain flour and self-raising flour different?

Self-raising flour has a couple of extra ingredients. It will have a ‘raising agent’ and, sometimes, salt added to it. Plain flour is…well…plain. If you want to use it in recipe which requires your bake to rise, you’ll need a separate raising agent.

What is a raising agent?

A common raising agent used in foods (when baking) is baking powder. Baking powder contains two active ingredients, one alkali and one acid. Bicarbonate of soda (sodium bicarbonate), which is the alkali, and cream of tartar, an acid (not to be confused with cream of tartarewhich is a condiment which accompanies fish!).

Self-raising flour has the raising agent added to it already, typically baking powder (roughly one teaspoon for every 100g of flour).

Whereas bicarbonate of soda can be used as a raising agent, if you don’t have other acidic ingredients like lemon juice or vinegar, or if you use too much, it can end up tasting a bit soapy. No-one wants a soapy-tasting scone.

Can I swap plain flour for self-raising flour?

Err, no. Not if you want whatever you are baking to rise. These ingredients, whilst both a white powder you use for baking, cannot be swapped without adding additional ingredients. As explained above, if you only have plain flour in the cupboard but the recipe calls for self-raising, you will need to add a raising agent separately.

Do I need the same amount of raising agent regardless of the recipe?

Good question. If you were baking something which had ‘heavy’ or wet ingredients in it, like pieces of fruit or fruit puree, you might need more.

Check your cupboards

Regular bakers will know the pain of realising you have two or three packets of the same flour open at the same time. Whilst flour takes a long time to go off, bear in mind that – eventually – the raising agents within self-raising flour will expire. Your bakes might look a little sad if the flour is out of date.

Gluten-free flour

If you suffer from a gluten intolerance or have Coeliacs, you can swap your standard plain or self-raising flours with gluten-free versions.