He began at CSIRO as a Technical Assistant Grade 1 (Junior), and was appointed a Chief Research Scientist in 1992 at the age of 55.
[1] After joining CSIRO in 1954, he became a part-time student at the University of New South Wales (UNSW), where he studied food technology.
[7] His thesis advisor was Martin Wesley Miller (1925–2005) in the UC Davis department of food science and technology.
[8] After completing his Ph.D., Pitt spent a postdoctoral year at the USDA's Northern Regional Research Laboratory (NRRL), where his supervisor was Clifford William Hesseltine (1917–1999).
[1] Pitt used many fungal cultures obtained from NRRL during his postdoctoral fellowship to establish a yeast and mold collection at CSIRO, which by the year 2021 had about 6000 specimens.
[13] From the 1970s to 1990s, Pitt and Hocking did pioneer research on methods for isolating and identifying foodborne fungi, as well as their physiology and ecology.
[4] He, with his frequent collaborator Ailsa D. Hocking, researched ways to prevent food spoilage caused by the fungal genera Aspergillus, Penicillium, and Cladosporium, along with the yeast species Zygosaccharomyces bailii[15][16][17] [18][19] Pitt was the author, coauthor, editor, or co-editor of 20 books and the author or coauthor of about 250 research papers or book chapters.
He won several awards, most notably the Commonwealth of Australia's Centenary Medal with citation for "services to food science and technology".