Complex sentence: Infantile scurvy emerged in the late 19th century because children were being fed pasteurized cow's milk, particularly in the urban upper class--the pasteurization killed bacteria but also destroyed vitamin C. This was eventually resolved by supplementing with onion juice or cooked potatoes.
Split into simpler sentences: Infantile scurvy emerged in the late 19th century because children were being fed pasteurized cow's milk, particularly in the urban upper class. While pasteurization killed bacteria, it also destroyed vitamin C. This was eventually resolved by supplementing with onion juice or cooked potatoes.