Everyone has bought a package of commercial household flour and then wondered what the label “wheat flour type 550” is all about. Not only the type of grain – such as wheat or rye – but also the so-called “type designation” provides information about the nature of the flour.
Small flour sort and type lore
So let’s briefly trace the path back to the mill: in flour production, the cleaned grain is ground between two different, fast-running grinding rollers. The grain can be ground to different finenesses in the process. Flour, baking meal, whole-grain meal or whole-grain flour remain in different proportions.
If the fineness of the milled grain is less than 180 micrometers, it is referred to as type flour. The degree of milling indicates the percentage of a particular type flour that is left over in relation to 100 kilograms of the original grain.
The higher the degree of milling, the darker, richer in protein, fiber and minerals the flour is. The lower the degree of milling, the lighter and starchier the flour.
Determining the lightness or type is done by determining the mineral content. When flour is burned at about 900 degrees Celsius, the minerals are left behind as “ash.”
Not all flour is the same
According to the amount of these residues, the different types of flour are designated with numbers. Thus, 100 grams of wheat flour type 550 contains an average of 0.55 grams of minerals in the dry matter.
While the type flours have a minimum shelf life of one year or more, the wholemeal flours should not be stored for more than four to six weeks.
In addition to wheat and rye flours, the cereal types spelt, triticale – a cross between wheat and rye – as well as barley, oats and corn are mainly used for bread production. (aid)
