Task mass balance
Task 1)
In a production of lactic acid products, lactic acid lactic acid is produced during growth by the
production organism S. lactis, which has the following composition CH1,8O0,5N0,2. In the
fermentation, on basis of lactose a yield of 0.22g biomass / g substrate and 0.39g lactate / g
substrate is obtained.
The production follows the equation below:
C12H22O11+ aO2+ bNH3
cCH1,8O0,5N0,2 + dCO2 + eH2O + fC3H6O3
a) Write the mass balance for the elements
b) Determine the stoichiometric coefficients
Task 2
Growth of Saccharomyces cerevisiae under anaerobic conditions produces both biomass and
product. The process follows the reaction equation below. 0.291g of product is generated per
gram of glucose
C6H12O6 + b NH3  cCH1.7 O0.5 N0.2+ f CH3O0,7 + dCO2 + eH2O
a) Write the mass balance for the elements
b) How much CO2 (specified as YCO2/S) is produced in the process ?
c) Determine the stoichiometric coefficients