CELL IMMOBILIZATION - APPLICATION TO ALCOHOL PRODUCTION

The immobilization of whole cells is a technique that can be used in several production processes, among them alcoholic fermentation. By concentrating an active cell biomass in a bioreactor, the efficiency of bioconversion increases, as does the reactor productivity which, in turn, results in the reduction of the reactor size for a given production rate. Immobilization can be carried out in different ways; adsorption and entrapment in gelatinous matrices are the methods most commonly used. These techniques can be applied to practically all of the viable and non-viable whole cells systems of interest. Several reactor configurations are used successfully; many more have been proposed. Fermentor design imposes limitations on immobilization processes, requiring study of such aspects as mass-transfer, growth of cells in the reactor, aeration and backmixing.