La tasa de absorción de agua de la harina se entiende por el volumen máximo de adición de agua cuando cuatro se convierten en masa, indicado por porcentaje (%). La tasa de absorción de agua tiene una influencia directa en la tasa de producción de alimentos. Para productos de harina, como bollos al vapor y pan., cuanto más se absorbe el agua, El mayor número de bollos al vapor y pan del mismo peso de harina es. Muchos factores influyen en la tasa de absorción de agua de la masa: principalmente disposición de granulado de harina, contenido de proteína, Polisacáridos de no escenario, daño al almidón, contenido de agua, etc.. De los cuales hay tres factores más importantes: contenido de proteína, starch damage and non-starch polysaccharides.

The protein in flour is categorized as water soluble protein and water insoluble protein (gluten protein). Researches show that water soluble protein and water insoluble protein both absorb water, but the water absorption of water insoluble protein (gluten protein) is more important and has a great bearing on dough’s water absorption rate. When water insoluble protein absorbs water, it can form a viscoelastic network structure unique to dough. Starch damage means the damage of starch’s outer cell membrane caused by mechanical grinding and pressing during milling process. Damaged starch is decomposed into dextrin, maltose and glucose under the effect of acid and enzyme, which play an important role in water absorption during dough’s fermentation and baking periods. The water absorption rate of damaged starch can reach 200%, which is five times that of complete starch granules.

Obvious negative correlation exists between gluten content and dough’s water absorption rate; no correlation exists between water holdup rate and dough’s water absorption rate; while obvious positive correlation exists between damaged starch content and dough’s water absorption rate.

As damaged starch influences dough’s water absorption rate to great extent, damaged starch content is high and dough’s water absorption rate is high, and thus the production rate of flour products is high. Por lo tanto, damaged starch content should be increased properly in order to improve the production rate of flour products. Sin embargo, researches show that high starch damage rate will affect product quality, so damaged starch contents should be properly adjusted according to different usages of tailored flours.