This is low-protein, low-gluten white or wholemeal flour with a raising agent mixed in. The most usual raising agent added is baking powder, but some brands also use bicarbonate of soda or other agents.
Self-raising flour is widely available in UK supermarkets. Outside of the UK and USA, it is not commonly used.
Self-raising flour will not keep for very long. The baking powder absorbs moisture from the air, which reacts with other ingredients in the flour, affecting its ability to rise.
Self-raising flour is used in baking and cake-making, and is often an ingredient in packaged cake mixes. If you do not have self-raising flour, combine plain flour with baking powder and salt, or add raising agents separately in your recipe. Self-raising flour is often used as a short-cut in baking, or by vegans who do not eat eggs (the extra raising agent in the flour does the eggs’ work).
Article by Sejal Sukhadwala