Lipases (triacylglycerol acylhydrolases, EC 3.1.1.3) are versatileenzymes that are widely used in production of fine chemicals andother industrial processes [1–8]. All commercially relevant lipasesare produced as extracellular enzymes via microbial fermentationprocesses. Microbial lipases have been discussed extensively in theliterature [9–11].For a given producer species, the lipase titer depends on thebiomass concentration in the broth, the nutritional characteristicsof the culture medium and the other production conditions. A highconcentration of the microbial biomass is desired in a fermenta-tion to maximize the volumetric productivity of the enzyme andattain a high titer. High cell density fermentations (HCDF) have thepotential for enhancing lipase productivity and titer [12]. HCDFsdo have drawbacks [13]. For example, the control of culture con-ditions (e.g. dissolved oxygen concentration) can be difficult in anHCDF operation and this may adversely impact the production [12].Notwithstanding their shortcomings, high cell density operation isconsidered economically attractive overall [13].