Fresh, defrosted and deligniWed brewer’s spent grains (BSG) were used as yeast supports for alcoholic fermentation of molasses. Glucose
solution (12%) with and without nutrients was used for cell immobilization on fresh BSG, without nutrients for cell immobilization
on defrosted and with nutrients for cell immobilization on deligniWed BSG. Repeated fermentation batches were performed by the immobilized
biocatalysts in molasses of 7, 10 and 12 initial Baume density without additional nutrients at 30 and 20 °C. Defrosted BSG immobilized
biocatalyst was used only for repeated fermentation batches of 7 initial Baume density of molasses without nutrients at 30 and
20 °C. After immobilization, the immobilized microorganism population was at 109 cells/g support for all immobilized biocatalysts. Fresh
BSG immobilized biocatalyst without additional nutrients for yeast immobilization resulted in higher fermentation rates, lower Wnal
Baume densities and higher ethanol productivities in molasses fermentation at 7, 10 and 12 initial °Be densities than the other above biocatalysts.
Adaptation of defrosted BSG immobilized biocatalyst in the molasses fermentation system was observed from batch to batch
approaching kinetic parameters reported in fresh BSG immobilized biocatalyst. The results of this study concerning the use of fresh or
defrosted BSG as yeast supports could be promising for scale-up operation.
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