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The influence of shear rate and concentration on the viscosity of solutions of native potato starch in water was investigated. The concentration dependence of viscosity was expressed by the Huggins equation with shear rate independent intrinsic viscosity. On the other hand the Huggins parameter is strongly influenced by the shear rate and decreases with the reciprocal square root of increasing shear rate in the range from 50.1/s to 1000‐1/s.

This work presents a novel design of a continuous crystallizer, the Archimedean screw crystallizer reactor (ASKR) with integrated Archimedean screw as conveying element. By the screw, the axial motion of the product solution is initiated, and an undesired axial mixing is restricted. This structure results in a narrow residence time distribution and, thus, promotes a defined product quality. In order to quantitatively assess the flow characteristics of the crystallizer and to highlight the influence of variable operating parameters such as rotational speed and volumetric flow, investigations of the residence time behavior with variation of the operating parameters are reported.

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In this paper enzymatic hydrolysis reactions have been considered as integration-limited reactions analogous to crystal growth. Based on the mathematical formulation of diffusion of polysaccharide substrate molecules to binding sites of the enzyme, integration kinetics were derived and compared to measured data. Significant is the measured and calculated decrease of the ratio of the specific activity and the Michaelis-Menten parameter with increasing molar mass of the enzymes with an exponent more than unity.