Microbiological Safety of Cheese Made from Heat-Treated Milk, Part I. Executive Summary, Introduction and History

Research on pasteurization of milk for cheesemaking was begun in the late 1800's. Early equipment was crude and control devices non-existent. Consequently, early pasteurization processes were not well verified. Commercial application was slow, except in New Zealand, where almost the entire cheese industry converted to pasteurization in the 1920's. In the United States, debate on the merits of pasteurization continued for years. Demand for cheese during World War II and foodborne disease outbreaks caused by cheese stimulated promulgation of government standards which included the options of milk pasteurization or 60 d holding at a minimum temperature of 2°C (35°F). The cheese industry has continued to improve technology, including that which is safety related. United States production of cheese has continued to expand, from just over 1 billion pounds in 1948 to 5.4 billion pounds in 1987. Thirty-eight percent of the 1987 total comprised varieties wherein heat-treated milk is frequently utilized.