Maltose Production from Soluble Starch by β-Amylase and Debranching Enzyme Immobilized on Ceramic Monolith

Hydrolysis of soluble starch by β-amylase and debranching enzyme (pullulanase or isoamylase) immobilized on a ceramic monolith were carried out in batch and continuous reactors at pH 4.8 and 40°C. In batchwise reaction, reactant solution was stirred by a basket impeller involing three of the immobilized enzyme monolth under the condition of negligible external diffusion effect. To improve the maltose yield, a method to immobilize the enzymes efficiently on ceramic monolith was examined. Also, an associated model of the reaction kinetics for the two free enzymes discussed in our previous paper and pore diffusion phenomena was proposed and its agreement with time course data of maltose formation was investigated. Continuous production of maltose was conducted in a co-immobilized reactor, wherein ten blocks of immobilized enzyme monolith were stacked, at starch concentrations ranging from 5 to 100 kg· m^-3. As a result, it was found that efficient production of maltose was performed in the immobilized enzyme monolithic reactor.