Fig. 3
Overall performance of the flux-based Micro-aerated Control. a Respiratory quotient (RQ), oxygen flux (\({\text{J}}_{{{\text{O}}_{2} }}^{\text{CA}}\)), and carbon dioxide flux \(\left( {{\text{J}}_{{{\text{CO}}_{2} }}^{\text{CA}} } \right)\) in FMC fermentation. The arrows indicate the activation of the RQ loop, which was deactivated when RQ returned to the set boundaries (lower boundary: red dashed line, upper boundary: blue dashed line) or when DOT \(\ge\) 4.5%. b QN2 and QAIR flow rates during the feeding phase and up to the end of the cultivation. c Fresh medium feed flow rate and substrate flux \(\left( {{\text{J}}_{\text{S}}^{\text{CA}} } \right)\) in FMC fermentation