• Flour

Flour is the base of a wide variety of baked goods. The property of each type of flour greatly affect the texture, structure, and flavour of the final product, so understanding the composition of types of flours is crucial to achieve success in baking.

Milling Process

The milling process is the procedure used commercially to transform wheat grains into flour.

  1. Cleaning: Wheat is cleaned to remove stones, sand and other impurities from the mixture
  2. Mixing: Different varieties and protein contents of wheat are mixed to achieve desired characteristics.
  3. Tempering: Wheat is treated with water and allowed to rest for hours, softening the bran and making the endosperm easier to separate. The bran is the outer layer of the wheat grain, whereas the endosperm is the large, central part of the grain.
  4. Break rolling: Wheat grains are passed through 2 cast steel break rollers, where the top roller runs at a slightly faster rate than the lower roller. As a result, a shearing motion is created, opening up the wheat grains. This provide better access to the endosperm.
  5. Separation: The fragments of wheat grains are separated by size and weight, isolating the bran, endosperm and germ. The germ is the small inner part within the endosperm, at the base of the wheat grain.
  6. Further grinding: These components are ground into smaller particles by passing them through the break rollers again.
  7. Combining components: bran and germ might be added back to the endosperm to form whole wheat flour.

Types of Flour

Flours are classified by their colour and intended use. Each type has unique characteristics affecting the texture, flavour, and nutritional content of baked goods.

  • Wholemeal flour: Contains 100% of each component of the wheat grain, including bran, endosperm and germ. As most fibre and protein are contained in bran and germ, wholemeal flour has higher nutritional values that other types of flour. However, bran and germ do not contain glutenin or gliadin and they would interfere with gluten development, so they might restrict gluten development. Also, wholemeal flour is more absorbent than white flour, so more liquid is required when using it.
  • White whole wheat: Made from a paler variety of wheat, it is a whole flour containing all components of wheat, but has a lower tannin content resulting in a lighter colour.
  • White flour: Made entirely from endosperm, white flour consists of finer flour particles and so they would not burst air bubbles in baked products, creating light and fluffy baked goods.
  • Brown flour: White flour with some bran and germ added back in, offering more nutritional content than white flour but less than wholemeal flour.
  • Bread flour: Contains 12-15% of protein content which helps gluten formation. It also has elastic properties, stabilising and strengthening air bubbles formed in baked goods. Bread flour is ideal for baked goods with a chewy consistency, including pretzels, bagels and baguette.
  • Pastry flour: Has a fine texture and 7-9% of protein content, pastry flour has less gluten content allowing a light texture to be produced in baked goods. It is commonly used in pie crusts, breadsticks and pound cakes.
  • Cake flour: Ultra-fine consistency with 6-8% protein, often bleached to absorb more liquid and rise higher. It is ideal for tender cakes.
  • All purpose flour: Made from endosperm, all purpose flour has 10-13% of protein content, making it more shelf-stable. It is commonly used for a wide range of baked goods including cookies, brea, cakes and muffins.
  • Self-raising flour: Produced by mixing all purpose flour with leavening agent, such as baking soda and salt. This is done during the milling process, making it suitable for biscuits, scones, pancakes, cakes and muffins.
  • Strong flour: With 13-14% protein content, strong flour is milled more coarsely so a lot of kneading is required to form a strong and supple dough structure. It is commonly used in bagels, pretzels doughnuts and shaped pasta such as orzo.
  • 00 flour: Finely ground durum wheat with 11-12% protein content, 00 flour has strong but less elastic gluten, producing less chewy baked goods. This makes it ideal for pasta, gnocchi, lasagna, pizza, flatbread, focaccia and crackers.
  • Rye: Light rye only uses the starchy endosperm of rye grains, producing light and airy dough; dark rye used whole kernel, producing heavy and dark dough. It has approximately the same amount of protein as wheat but only a small proportion forms gluten. Rye is also high in polyunsaturated fatty acids so rye oil oxidises easily producing rancid off flavours. Hence, rye flour must be kept fresh. It is usually used in rye bread, crackers and sourdough starter.
  • Bleached flour: Treated with chlorine or benzoyl peroxide to damage its starch and protein content, this can speed up the curing process for a less gummy and more malleable dough that absorbs more liquid.
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