Process development of starch hydrolysis using mixing characteristics of Taylor vortices

Abstract

In food industries, enzymatic starch hydrolysis is an important process that consists of two steps: gelatinization and saccharification. One of the major difficulties in designing the starch hydrolysis process is the sharp change in its rheological properties. In this study, Taylor-Couette flow reactor was applied to continuous starch hydrolysis process. The concentration of reducing sugar produced via enzymatic hydrolysis was evaluated by varying operational variables: rotational speed of the inner cylinder, axial velocity (reaction time), amount of enzyme, and initial starch content in the slurry. When Taylor vortices were formed in the annular space, efficient hydrolysis occurred because Taylor vortices improved the mixing of gelatinized starch with enzyme. Furthermore, a modified inner cylinder was proposed, and its mixing performance was numerically investigated. The modified inner cylinder showed higher potential for enhanced mixing of gelatinized starch and the enzyme than the conventional cylinder.

Citraconylation and maleylation on the catalytic and thermodynamic properties of raw starch saccharifying amylase from Aspergillus carbonarius

“…The modified enzyme can be used in a continuous process of starch saccharification at varying temperatures depending on the gelatinization temperature of the grain/tuber starch used in a given process (operating temperature should be below the gelatinization temperature). The wide difference between the velocity of the starch during gelatinized and saccharification makes the design of a continuous starch saccharifying process very difficult [ 49 ]. Applying a stable raw starch digesting enzyme in this instance promises to save energy and facilitate ease of processing.…”

Flow dynamics in Taylor–Couette flow reactor with axial distribution of temperature

“…This implies that the local increase in temperature occurs at the initial section where the reaction heat is produced, if a continuous TCFR with an axial flow is applied to such a reaction system. The axial distribution of temperature in the continuous TCFR can be also seen in food processes like starch hydrolysis where a cooling subsequently to a heating in one apparatus is necessary . As a result, a buoyancy flow which complicates the flow pattern in the TCFR is generated because of this axial distribution of the temperature.…”

Numerical Simulation of Sterilization Processes for Shear‐Thinning Food in Taylor‐Couette Flow Systems

“…After that, η eff and Re eff are obtained easily, in turn. According to Masuda et al , , in non‐Newtonian fluid systems, Re eff calculated by the above procedure is suitable from the practical viewpoint.…”