stärkelsekorn

Stärkelsekorn, also known as starch granules, are discrete storage units of starch found in plant cells. They are composed of amylose and amylopectin, two polymers of glucose. Starch is the primary carbohydrate reserve in plants, serving as a readily available energy source. Stärkelsekorn vary in size, shape, and structure depending on the plant species and the specific tissue. For instance, starch granules from potato tubers are typically large and oval, while those from cereal grains like wheat or rice are smaller and often polygonal. The characteristic shape and presence of growth rings within a stärkelsekorn can often be used for identification purposes.

The formation of stärkelsekorn occurs within plastids, specifically amyloplasts. Glucose units are synthesized and then polymerized into amylose and amylopectin. These polymers then aggregate and precipitate within the plastid, forming the granule. The process is regulated by various enzymes, and the structure of the granule reflects the organized layering of these starch molecules. Stärkelsekorn are insoluble in water at room temperature, but they swell and can eventually gelatinize when heated in water, a process that is crucial in cooking and food processing. This gelatinization is responsible for the thickening properties of starch in sauces and gravies. Furthermore, stärkelsekorn can be digested by amylase enzymes in animals, releasing glucose for energy.