*This post first appeared on The PediaBlog on June 29, 2016.
Got (Raw) Milk?
(Calvin and Hobbes by Bill Watterson/Yahoo!Images)
Last month, the American Academy of Pediatrics reported on a serious outbreak of diarrhea due to infections with the bacteria Campylobacter jejuni. From May-November, 2014, ninety-nine cases of C. jejuni infection were reported in Utah, one of the only states in the U.S. where the commercial sale of raw milk is permitted. All the infected patients had one thing in common: they drank raw (unpasteurized, non-homogenized) milk, or ate processed cheese from one dairy farm in that state. As a result of this outbreak, ten people were hospitalized and one developed multi-system organ failure and died.
Pasteurization of milk from cows, sheep, and goats began almost 100 years ago in response to the ease in which severe, even fatal intestinal bacterial illnesses were acquired from unprocessed, raw milk. Today, according to the AAP:
An estimated 3% of the U.S. population drinks raw milk. Infants, young children, the elderly, pregnant women and people with weakened immune systems are at greatest risk of becoming ill from consuming raw milk, but healthy people of any age also may become ill or die from ingesting contaminated raw milk.
Alison Spiegel explains how pasteurization works:
Pasteurization is the process of heating milk up and then quickly cooling it down to eliminate certain bacteria. For effective pasteurization, milk can be heated up to 145 degrees Fahrenheit for 30 minutes, but this method isn’t very common. More common is heating milk up to at least 161.6 degrees Fahrenheit for 15 seconds, which is known as High-temperature Short-Time (HTST) pasteurization, or flash pasteurization. This method will keep milk fresh for two to three weeks. Then there’s Ultra-Heat Treatment (UHT), whereby milk is heated to 280 degrees Fahrenheit for a minimum of two seconds. This processing results in a shelf life that can extend up to nine months. Milk treated with pasteurization or HTST is labeled as “pasteurized,” while milk treated with UHT is labeled as “ultra-pasteurized.”
Once pasteurization is complete, Spiegel says, the homogenization process begins:
The purpose of homogenization is to break down fat molecules in milk so that they resist separation. Without homogenization, fat molecules in milk will rise to the top and form a layer of cream. Homogenizing milk prevents this separation from occurring by breaking the molecules down to such a small size that they remain suspended evenly throughout the milk instead of rising to the top.
Over the years I have met families who drink raw milk from their own farms. They all say it tastes much better than the processed store-bought varieties and many believe it is a much healthier product as well. Julie R. Thomson breaks down the pros and cons of raw milk and says that even though raw milk, and cheeses and yogurts derived from raw milk, might taste better, “there is no strong scientific evidence that raw milk is healthier, so why risk it?”
While many raw milk enthusiasts cite studies that claim raw milk can help prevent asthma, lactose intolerance and allergies, those who are against raw milk consumption point out that these studies have been small and inconclusive.
The U.S. Food and Drug Administration spills the beans on raw milk and pasteurization:
Here are some common myths and proven facts about milk and pasteurization:
- Pasteurizing milk DOES NOT cause lactose intolerance and allergic reactions. Both raw milk and pasteurized milk can cause allergic reactions in people sensitive to milk proteins.
- Raw milk DOES NOT kill dangerous pathogens by itself.
- Pasteurization DOES NOT reduce milk’s nutritional value.
- Pasteurization DOES NOT mean that it is safe to leave milk out of the refrigerator for extended time, particularly after it has been opened.
- Pasteurization DOES kill harmful bacteria.
- Pasteurization DOES save lives.
Read everything you would want to know about raw milk from the Centers for Disease Control (CDC) here.