Cowan has been at the company for 16 years, joining as general manager before moving up to the position of operations manager 12 years ago.
He has also been on the company’s board since 1990.
Prior to joining Anthony Rowcliffe & Son, Cowan worked as general manager for fine foods company Robinski.
In his new role, he will take responsibility for the day-to-day management of the company.
Tim Rowcliffe, chairman of Anthony Rowcliffe & Son, who had previously taken responsibility for the managing director role in addition to his chairman activities, said: “Milton has played a key role in growing and diversifying the company’s business.”