[4] These bioreactors uses a membrane to separate products from the rest of the reactor, limiting their inhibition.
A downside to external loop reactors is they create additional shear stress.
[7] Integrated liquid-liquid extraction can be used to remove products that have a density that differs from the rest of the bioreactors contents.
When the liquid in the vessel is placed in vacuum conditions the ethanol begins to evaporate because its more volatile than the rest of the reactor contents.
This technique requires an acclimation period for the yeast in the reactor to adapt to the lower pressure environment.