category: food/groceries: sugar

Beet Sugar, de.: Rübenzucker

Beet sugar is produced from sugar beets. Their roots are is high in nutrients, contains up to 22 percent of sugar and is commercially grown all over Europe.

Production of beet sugar

Sugar beets are harvested in September. They are washed and sliced into thin strips called cossettes. Then these cossettes are warmed in so-called diffusers with hot water. When the beets reach about 70 °C, sugar dissolves from the cells. The raw juice is then separated from the pulp.

The raw juice contains other soluble matters besides sugar, which are unwanted in the finished product. Minerals, different acids, invert sugar and proteins are among them. To remove those non-sugar matters lime and carbon dioxide are added to the raw juice. This treatment precipitates particles that can now be filtered from the juice. A clear, light golden sugar solution called thin juice with a sugar content of up to 16% and calcium carbonate are left.

The thin juice is then thickened in several stages of evaporation, until a golden brown thick juice with a sugar content of 67% is derived. This thick juice is seeded with fine sugar crystals and heated at a temperature of 75 °C until the fine crystals have grown to large golden sugar crystals. These crystals are still covered with syrup. This mixture of syrup and crystals is called magma by experts.

The magma is centrifuged with steam to separate the crystals from the syrup. The sugar obtained is called raw sugar and has a yellow to brown colour. To produce white refined sugar, this raw sugar is dissolved and the obtained pure sugar solution is crystallized again. This last crystallization process is repeated until white sugar of good quality forms. Dissolving and crystallizing again is called refining, the finished sugar is therefore called refined sugar.

By-products of the sugar production are used for other purposes: The pressed and dried pulp of the sugar beets is sold as animal feed. Calcium carbonate from clearing the juice is an excellent and cheap fertilizer.