Ethanol production using an immobilized cell system has some
advantages when compared with free cell culture. The reaction
speed can be accelerated, a high dilution rate can be used in continuous fermentation without cell washing and it is less susceptible to the effect of inhibitory compounds and nutrient depletion
[7]. Different immobilization techniques such as entrapment in
Ca-alginate beads, agar agar and k-carrageenan have been used
extensively in fermentation industries for producing various bio-products such as amino acids [8], enzymes [9], organic acids [10]
and ethanol [4].