Milling
When wheat kernels are milled, there are several steps that must be taken to ensure top quality.
Cleaning the Wheat
- Separates wheat from seeds and other grains, gets rid of foreign materials such as metal, sticks, stones and straw.
Tempering
- Moisture is added in precise amounts to toughen the bran and mellow the inner endosperm. This makes the parts of the kernel separate more easily and cleanly.
Entoleter
- A machine breaks and removes unsound wheat from the mill flow.
Grinding
- Wheat is fed from bins to the “rolls” or corrugated rollers made from chilled cast iron.
- Middlings are separated by size by a sifter that shakes the particles through series of bolting cloths or screens to separate the larger from the smaller, and each size returns to corresponding rollers. This process is repeated until the desired particle size of flour is obtained.
Purifiers
- A controlled flow of air lifts off bran particles while at the same time a bolting cloth separates and grades coarser fractions by size and quality.
Bleaching
- Most flour is exposed to chlorine gas or benzoyl peroxide to whiten and brighten flour color. However, some companies, such as King Arthur Flour, allow their flour to age (whiten) naturally.
