A system was developed to continuously acidify and inoculate skim milk for the production of fresh cheese. Four strains of mesophilic lactic acid bacteria were entrapped separately in κ -carrageenan/locust bean gum gel beads and used in a stirred bioreactor operated at 26°C with a 25% (v/v) gel load. The pH in the reactor was controlled at 6.0 by adding fresh milk using proportional integrated derived regulation. The bioreactor was operated during 8-h daily cycles for up to 7 weeks with different milks (heat treatment, dry matter content) and differing starting procedures. The heat treatment of the milk was an important factor for process performance: a dilution rate increase of 57% and an inoculation level decrease of 63% were observed with sterilized UHT skim milk (142°C – 7.5s) compared with pasteurized skim milk (72°C – 15s). The dry matter content of the milk (8–13% w/w) had no detectable effect on these parameters. A convenient starting procedure of the system was tested; steady-state was reached in less than 40 min following an interruption period of 16–60h. These results combined with our published data on process performance show the feasibility of using an integrated immobilized cell bioreactor for milk prefermentation in cheese manufacture.