Wheat Flour comes in various grades, including:
- Wholemeal Flour: this is flour that contains all its bran and germ. Wholemeal flour is more nutritious than white flour.
- Brown Flour or Wheatmeal Flour: this is midway between white and wholemeal flours.
- White Flour: this is wheat flour which has had its bran and wheatgerm removed. Sometimes white flour has synthetic minerals and vitamins added back into the flour to "enrich" it - calcium, iron, niacin, vitamin B1. White flours are further differentiated as:
- Strong Flour or Bread Flour: this is flour that has blends of hard wheat only and has 12-14% or more of protein.
- All-Purpose Flour (US only): this is flour that has been made from a blend of hard and soft flour, with protein content of 10-12%.
- Plain Flour or Cake Flour: flour that has been only with soft flour, so has 9% protein.
- Self-Raising Flour or Self-Rising Flour: flour that contains baking powder to enable it to raise without adding in a raising agent. Self-raising flour has a limited shelf life because moisture absorbed into the flour results in the baking powder reacting and so depleting its efficacy.
Davidson, A. (1999) The Oxford Companion to Food, Oxford University Press. ISBN 0192115790.