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The use of immobilized yeast is a promising technique for ethanol production. Studies have shown that immobilized cells have higher resistance to temperature, concentration of substrates and metabolites and a high yield for ethanol fermentation with higher activity. The proposal of this work is to immobilize Saccharomyces cerevisiae cells in calcium alginate and chitosan covered calcium alginate beads in order to observe the behavior of these beads for ethanol production. ഀ The fermentation media was made of glucose 100g/L solution; 100g of beads containing approximately 50 g of cells (wet weight) were used in a batch reactor placed in an orbital shaker, at 200 rpm and, 30°C. The conversion time was approximately 6 hours for all runs. However, every fermentation cycle was run for 10 to 12 h. After each cycle, the beads were washed with distillated water and placed in a new fermentation media. After each fermentation cycle, the ethanol concentration was 40g/L. ഀ Chitosan covered calcium alginate beads showed a longer conversion time and a slightly higher integrity of beads after eight fermentation cycles. Both calcium alginate and chitosan covered calcium alginate beads increase in volume during the fermentation cycles and show similar ethanol production.ഀ ഀ Supported by:ഀ CAPES - CNPq - FAPESP ഀ