In addition to their nutritional importance, starches present an important technological role in processed foods. The starches' functional properties, such as the relation starch-water, gelatinization temperature, gel formation and paste viscosity are of fundamental importance to define their industrial uses. On the other hand, the composition and structure of starch granules vary considerable according to their botanical source, affecting the properties and functions of starches in different products. The Peruvian carrot starch is considered to be easy of cooking, presenting low gelatinization temperature and high peak viscosity. It also presents low tendency to retrogradation and sineresys, what contributes to its high digestibility. Several techniques have been used to characterize viscosity changes during starch suspensions gelatinization, with the Brabender viscoamylograph being the most used instrument. Nevertheless, due to the complex system geometry, which difficult the mathematical description of flow inside the sample cup, measures of fundamental rheological properties can not be obtained. The aim of this research project is to evaluate flow properties and viscoelastic parameters of Peruvian carrot starch pastes as affected by concentration, temperature and gelatinization time through rheological measurements in a rotational rheometer operating under steady state shear and under small amplitude oscillatory shear.
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