Fermentation performance of free and immobilized yeast on cork(Sonneratia caseolaris) root – application of immobilized yeast to repeated batch ethanol fermentation

The immobilized yeast on cork (Sonneratia caseolaris) root grew better and exhibited higher fermentation rate than the free yeast. In the repeated batch fermentation, the immobilized cell system could be reused at least for ten cycles. The sugar uptake rate of the immobilized yeast gradually increased from 2.35 g/L.h (cycle 1) to 3.31 g/L.h (cycle 10). Similarly, the ethanol production rate of the fixed yeast augmented during the ten cycles and achieved maximum level of 1.38 g/L.h at cycle 10.