George Malcolm Trout was born on March 7, 1896 to Sidney and Anna Trout on a farm near Birmingham, Iowa. He attended the University of Northern Iowa from 1916-1917 and taught in a rural school from September 1917 to February 1918. He entered the U.S. Army in 1918 and served in France. He received his B.S. in Dairy Industry in 1923 and a M.S. in 1924 from Iowa State University. From 1924 to 1928 he was an instructor and assistant professor at University of West Virginia. He married Agnes Crain on September 1, 1927 and they had a son, James, and a daughter, Nelda.

Trout came to Michigan State College (now Michigan State University) in 1928 as an assistant professor of dairy husbandry. In 1936 while on leave from MSC, he received his Ph.D. from Cornell University. In 1936 he was made associate professor and then professor in 1941. In 1929 he researched and developed a homogenization process for milk. He discovered that for homogenized milk to taste good it must be pasteurized first. He wrote a book called Homogenized Milk which became a respected book on the subject.

In 1960 he moved to the Department of Food Science and Human Nutrition. He retired in 1966. Trout died November 1, 1990 at the age of 94.

In 1945 he received the Borden Award. In 1964 he received the American Dairy Science Association Award of honor. Trout's 90th birthday, March 7, 1986, was declared "Mac Trout Day" by Governor Blanchard. The Food Science building on the MSU campus was renamed for Trout on October 26, 1992.