Ethanol production from carob pod extract by immobilized Saccharomyces cerevisiae cells on the mineral kissiris

The production of ethanol from carob pod extract by immobilized S. cerevisiae cells on the mineral kissiris was investigated. The optimum conditions for carob pod extract fermentations were pH 3.5 - 6.5, temperature 30 degrees C and initial sugar concentration of 250g/l. A maximum ethanol concentration (64.5g/l), ethanol yield (28.3%) and sugar utilization (94%) was achieved at an initial sugar concentration of 250, 200 and 250g/l, respectively. In repeated batch fermentations, the immobilized S. cerevisiae cells on kissiris retained their ability to produce ethanol for 30 days.