Amyloza

Amyloza, or amylose in English, is a linear polysaccharide that serves as one of the two main components of starch. It is composed of D-glucose units linked predominantly by α-1,4 glycosidic bonds, forming mostly unbranched chains that can contain hundreds to thousands of glucose units. In starch, amylose is present alongside amylopectin, a highly branched polymer of glucose with both α-1,4 and α-1,6 linkages.

The amount of amylose in starch varies by plant source. Cereals such as wheat and maize typically contain about 20–30% amylose, while high-amylose varieties can reach higher percentages. Potato starch and many tropical tubers have relatively lower amylose content. The linear structure of amylose favors the formation of helical conformations in solution and contributes to specific textural properties in foods and gels.

In physical terms, amylose is less soluble in cold water than amylopectin, but when heated it leaches from starch granules and can form viscous pastes and gels as it cools and retrogrades. In starch granules, amylose can influence gelatinization, gel strength, and film formation, affecting texture and stability in processed foods.

Digestively, amylose is hydrolyzed by α-amylase to shorter sugars such as maltose and glucose, generally more slowly than amylopectin due to its linear structure. Higher amylose content often leads to the formation of resistant starch, which can impact glycemic response and gut fermentation.

Amylose-rich starches find applications in food texture modification, biodegradable materials, and various industrial processes where controlled gelation and film-forming properties are desired.