Additives
Flour is a most natural, wholesome food. You may see the words 'flour treatment agent' on the list of ingredients in your flour. This improver is generally vitamin C (ascorbic acid), which makes the dough more manageable and ensures a well risen loaf with what's known as 'good volume'. Flour was once bleached using various bleaching agents, but these are not used today. Sodium hydrogen carbonate and calcium phosphate are the baking powders (raising agents) used in self-raising flour.
