When most of us return home from grocery shopping, we wash and rinse the food we just bought to remove any germs that found their way onto our produce. We do this because we know the simple process can do a lot for keeping us healthy. But some foods—like dairy products—are not so easily washed and must go through a heating process before being sold to ensure safe consumption.
Late last year, five California children—including two from Contra Costa County—became seriously ill after drinking raw milk. Three of the five were hospitalized with hemolytic uremic syndrome, a serious condition that could lead to kidney failure.
Pasteurization, developed in 1864 by Louis Pasteur, is a process that kills harmful bacteria for us. It's a simple process that heats foods—like milk—to a specific temperature (161°F) for a specific amount of time (20 seconds) and also allows us to keep food fresh for a longer period of time. Pasteurization is now the norm. In 1948, Michigan was the first state to enact requirements to pasteurize all dairy products. Currently, most states impose restrictions on raw milk suppliers, due to the risks involved.
Because something is raw does not mean it is organic, fresh or even healthy. The germs found in raw milk can cause E. coli, typhoid fever, tuberculosis and diphtheria.
And it's not just milk. Unpasteurized cream, ice cream, yogurt, pudding and soft cheeses can be dangerous and unsafe to eat, yet continue to be produced, sold and consumed. All of these products are processed in various ways and may come from cows, sheep, goats or—new to the market—camels.
There are a few misconceptions touted about drinking raw milk. Here are some things you ought to know about pasteurization and raw milk.
- Pasteurizing milk does not cause lactose intolerance or allergic reactions. Both raw and pasteurized milk can cause allergic reactions in people who are sensitive to milk proteins. Lactose is present in raw milk and pasteurized milk.
- Raw milk may contain dangerous bacteria.
- Pasteurization does not reduce milk's nutritional value.
- Pasteurization does kill harmful bacteria.
- Practicing good hygienic methods on dairy farms can reduce, but not eliminate, the risk of milk contamination. Milk can become contaminated and unsafe in many ways: cow feces coming into contact with the milk; infection of the cow's udder (mastitis); cow diseases (e.g. bovine tuberculosis); Bacteria that live on the skin of cows (e.g. staphylococcus); contaminated equipment; vermin (e.g. rodents and insects); and human contamination (ex. cross-contamination from hands or clothing).
- Bacteria (e.g. campylobacter) associated with the consumption of raw milk and other raw dairy products can be especially harmful to children.
Pasteurizing milk products is the only way to kill many of the bacteria that can cause people to become very ill. Additionally, studies have shown that pasteurization does not significantly change the nutritional value of milk, which is rich in proteins, carbohydrates and other nutrients. Proper home storage is also important. Pasteurized dairy products should be kept at or below 41 degrees. Remember to check expiration dates to ensure you do not eat products that may have spoiled.
You can watch firsthand the dangers of raw milk at http://www.cdc.gov/foodsafety/rawmilk/raw-milk-videos.html
Ms. DiMaggio is a Registered Environmental Health Specialist with the Environmental Health Division of Contra Costa Health Services.
Healthy Outlook is written by the professional staff of Contra Costa Health Services, the county health department. Send questions to series coordinator Dr. David Pepper at firstname.lastname@example.org. For more health information, go to www.cchealth.org.