Because of its wide distribution in nature, starch was used since an early period, not only as food, but also as a useful product in various practical and industrial applications. Furthermore, today such starches are also incorporated in numerous other products such as drilling fluids, pharmaceuticals, detergents, coatings, resins, etc. Production of the degradation products of starch, such as glucose and high DE (dextrose equivalent) syrup, has been a well-established commercial practice for a long time.
The recent upsurge in industrial production of mixtures of glucose and fructose as a sucrose substitute has created new demands for glucose. When glucoamylase is used, the reaction is always carried out batchwise. If a reactor can be designed employing immobilized glucoamylase, the reaction can then be operated continously. Immobilized enzymes have been studied in a variety of reactors such as CSTR's, expanded and fludized beds, hollow tubes, tubular membrane reactors, packed beds. Among these reactors we have chosen packed bed reactors for investigation, because of their simplicity and possible industrial applications. Therefore, diffusion resistance in immobilized enzyme reactors has been investigated extensively in recent years. The effect of heat of reaction and temperature change on a bound enzyme reactor have been studied.
But there was no study concerning with starch conversion, viscosity variation with the conversion and pressure drop in a reactor, which can provide valuable information for packed bed reactor. This work aims at binding relationships among these factors theoretically as well as experimentally. If the values of Km, Vm, Ki, and parameter a, b and also the relation between glucose concentration and viscosity with hydrolysis reaction for a starch-immobilized enzyme system are determined by experiment, we should be able to predict pressure drop for the packed bed for starch hydrolysis.
