Recent technological improvements have extended the application range of permittivity biomass measurements to bacterial fermentations in highly conductive media. With Lactobacillus casei, the effective biomass detection sensitivity of the FOGALE Biomass System is around 0.2 g/l (0.01 pF/cm). Fermentations growth kinetics of Lactobacillus casei can be recorded with good reproducibility and accuracy despite the high medium conductivity varying between 15 and 75 mS/cm, and the low cell concentration (< 6 g/l).