Pfizer pioneered large-scale penicillin fermentation, using deep-tank methods that made industrial production possible during World War II.
Before this breakthrough, penicillin was grown mainly in shallow containers, a slow method that produced very small quantities. Pfizer already had experience fermenting citric acid, and its scientists adapted that expertise to grow Penicillium in large, aerated tanks. Jasper Kane and his colleagues helped develop the process, while the company converted a vacant ice plant in Brooklyn into a penicillin factory.
The new approach required constant mixing, cooling, aeration, and control of contamination and foam. It also used improved fungal strains and nutrient sources such as corn steep liquor. Pfizer’s investment was risky, but the results were substantial: in 1943 and 1944, the company spent heavily on the process and became the world’s largest penicillin producer.
Pfizer was not the only company involved in wartime penicillin production. Merck, Squibb, Lederle, and others also manufactured the drug through a coordinated American effort. Pfizer’s distinctive contribution was pioneering and scaling deep-tank fermentation, which helped supply Allied forces, including troops landing in Normandy in 1944.