To cite this article: Gonawan, F. N. et al. (2018). Immobilised-β-galactosidase catalysed conversion of lactose on the membrane surface. J. Phys. Sci., 29(Supp. 1), 49–56, https://doi.org/10.21315/jps2018.29.s1.7
Galacto-oligosaccharides (GOS) can be synthesised via β-galactosidase (β-Gal) catalysed conversion of lactose. The reaction process was carried out in the membrane reactor system to improve the conversion by partial separation of the products and galactose inhibitor. The reaction rate was determined by the concentration of the solutes on the biocatalytic membrane and it was varied by manipulating the transmembrane pressure (TMP). The yield of GOS was highest at a TMP = 0.5 bar. It was found that the formation of gel layer at higher TMP (> 0.5 bar) reduced the mass transfer of solutes through the biocatalytic membrane. Therefore, the reaction rates were decreased although the separation of galactose inhibitor was improved. Hence, it is concluded that the mass transfer of solute is the determining factor to obtain a high yield of GOS.