Yield coefficients quantify the efficiency of converting substrate into biomass or product. They are defined as the ratio of specific rates.
Yield of Biomass on Substrate (Ysx):
Ysx = μ / rs
Units are often (g Biomass / g Substrate) or (C-mol Biomass / C-mol Substrate) if rates are in C-mol units.
Yield of Product on Substrate (Ysp):
Ysp = rp / rs
Units are often (g Product / g Substrate) or (mol Product / mol Substrate).
Where:
- μ: Specific growth rate (e.g., h⁻¹).
- rs: Specific substrate consumption rate (e.g., g S/g X/h or h⁻¹).
- rp: Specific product formation rate (e.g., g P/g X/h).
Note: Ensure consistent units for the rates when calculating the dimensionless yield coefficient.