Yeast cells are immobilized in a column and glucose is fed through the inlet at a concentration of 90 g/l. If all the glucose is consumed and we can…
Yeast cells are immobilized in a column and glucose is fed through the inlet at a concentration of 90 g/l. If all the glucose is consumed and we can treat this as an anaerobic fermentation with negligible cell growth, then the ethanol concentration at the outlet will be:
Select an option to attempt
Correct Answer: Option D
Explanation
Ethanol yield from glucose fermentation (Embden-Meyerhof-Parnas / yeast fermentation):Glycolysis + alcoholic fermentation (Saccharomyces cerevisiae):Molecular weights: Glucose = 180 g/mol; Ethanol = 46 g/molGiven: 90 g/L glucose = 90/180 = 0.5 mol/L glucoseFrom stoichiometry: 1 mol glucose → 2 mol ethanolNote: This is the theoretical maximum (100% yield). Actual fermentations achieve 90–95% of theoretical yield.Answer: 46 g/L ethanol from 90 g/L glucose.