He is best known for developing products and processes for McDonald's (including Chicken McNuggets), he was the executive Chef at the time and for his extensive involvement in charitable and philanthropic activities in Philadelphia and other parts of the United States.

[3] He established Keystone Foods, which was instrumental in developing the use of mass-produced frozen burgers in the late 1960s, and supplied these as well as chicken and fish products to McDonald's.

They were in dispute over whether the inventor of the Chicken McNugget (unbeknown to them) became extremely wealthy, or received nothing for the invention and is today "working in the basement for regular wage, thinking of some shit to make the fries taste better."

[6] Smaller business ventures for Lotman and his wife in his later years included the establishment of the Peppercorn restaurant in the small Pennsylvania town of Wayne in 2013.

[2][9] Throughout his life he was active in fund-raising for a variety of events and organizations, including the Aberdeen Dad Vail Regatta and the Prince Music Theater,[2] which he and his wife had been involved in bringing back into action after its bankruptcy in 2010.