The conversion of whey permeates to galacto-oligosaccharides (GOS) was studied by the enzymatic action of β-galactosidase from Aspergillus oryzae in a continuous flow packed-bed reactor. A novel method of enzyme immobilization involving covalent immobilization of β-galactosidase on 3-aminopropyl triethoxysilane(3-APTES)-modified glass beads was developed by the cross-linking method. The pH and temperature dependence of the enzymatic efficiency of the glass bead-immobilized enzyme was compared with that of the free enzyme. Increased pH and thermal stabilities were observed for the immobilized enzyme versus the free enzyme. The reusability of the enzyme immobilized packed-bed reactor was studied and only about 4.6% of GOS yield was lost after eight reuses. Repeated cycle reactions were also carried out to improve the formation of GOS. The results showed that the GOS formation increased and a maximum GOS yield of 39.3% with 56.4% lactose conversion was obtained after the 2nd cycle of passing.

通过米曲霉β-半乳糖苷酶的酶促作用研究了乳清渗透物向半乳糖低聚糖的转化在连续流填充床反应器中 通过交联法开发了一种新的酶固定方法，该方法涉及将β-半乳糖苷酶共价固定在3-氨基丙基三乙氧基硅烷（3-APTES）修饰的玻璃珠上。将玻璃珠固定酶的酶效率与pH和温度的依赖性与游离酶的pH和温度依赖性进行了比较。相对于游离酶，固定化酶的pH和热稳定性均得到提高。研究了固定化酶固定床反应器的可重复使用性，经过八次重复使用后，仅损失了约4.6％的GOS产量。还进行了重复循环反应以改善GOS的形成。结果表明，经过第二个循环后，GOS的形成增加，乳糖转化率为56.4％时，最大GOS产率为39.3％。