Encapsulation high cell concentration in the matrix and yet keep all the cells inside the capsule (S.H. Cheong.,1993).The encapsulated whole cell invertase could be used more than 25 times without loss of enzyme activity. Nevertheless, the encapsulation bead have a weak mechanically strength as the capsule is composed of a thin semi-permeable membrane. Semi-permeable membrane allows substances and products from cell activities to travel freely but prevent transportation of large proteins and enzymes to go in and out whithin the membrane. This property leads to the rupture of capsule and the discharge of immobilized cells in the harsh condition such as wastewater treatment system.