Main Breakthrough at Peoria
On November 26, 1941, Andrew J. Moyer, Peoria lab's expert on mold nutrition, succeeded (with assistance from Dr. Heatley) in increasing the yields of penicillin 10 times with corn steep liquor. Including this in the culture medium created a better growth medium than anything tried. Dissatisfied still, Moyer added milk sugar and again the Penicillium mold doubled. Moyer discovered how to use deep vats to grow cultures.