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Revised Script Are you scared of this cow? NO? How about
the nasty bacteria in its milk that could lead to paralysis? Before the 1800’s, drinking
milk fresh from a cow was a common practice that is now seen as a risky option. Today,
we have the luxury of modern science and pasteurized milk, but to many the process of pasteurization
still remains a mystery. Pasteurization may sound complicated but really,
it is nothing more than heating the milk to a certain temperature for a certain length
of time. There are three types of pasteurization used for milk. They differ mainly by the temperature
the milk is heated at and the length of time is it heated for. The three types of pasteurization
are High Temperature Short Time, Higher Heat Shorter Time, and Ultra Pasteurization. For
High Temperature Short Time pasteurization, the milk is heated to 1610F for 15 seconds.
This is the most commonly used method in the United States. In the case of Higher Heat
Shorter Time, the milk can be heated up to 2040F for .01 seconds, and Ultra pasteurized
milk is heated to 2800 for 2.0 seconds. So what does the heat actually do to the milk?
There is a general agreement among scientists that the heat from pasteurization kills certain
bacteria in the milk that makes us sick. Bacteria such as Brucella, Campylobacter, Listeria,
Salmonella, and Ecoli, are commonly found in unpasteurized milk and can lead to fever,
diarrhea, cramps, paralysis, or even death. A study done by Samia Elrahman and her colleagues’
shows that pasteurization indeed kills enough of these bacteria so we don’t get sick.
Their research was conducted by collecting 36 samples of unpasteurized milk and 12 samples
of pasteurized milk from Blue Nile Dairy Company farms. The samples underwent chemical and
microbial testing to determine how much dangerous bacteria was in the unpasteurized milk samples
compared to the pasteurized milk. Instead of measuring each kind of bacteria, they measured
the amount of coliform bacteria. Coliform bacteria do not directly cause illness but
do act as a red flag for dangerous bacteria. The more coliform present, the more bad bacteria
there is in the milk. Results showed that pasteurization caused a significant decrease
in coliform amounts. Even though most agree that pasteurization
makes milk safer, some still insist on risking their health and drink unpasteurized milk.
According to the website Real Raw Milk Facts, an awareness website reviewed by scientists
and health educators, the bacteria in unpasteurized milk has lead to many outbreaks of illnesses.
A research study of one outbreak was conducted at a Connecticut farm in 2008 by Alice Guh
and the Connecticut Department of Public Health. The goal was to confirm suspicion that an
outbreak of E.Coli 0157 was caused by the consumption of unpasteurized milk from the
Connecticut farm. To do this, they collected data in four different ways. They took stool
samples from customers, matched and compared two healthy control subjects for every one
confirmed sick subject, gave surveys about recent exposures, and inspected the milk holding
tanks. The stool samples were tested with culture methods to determine which customers
were sick with E.Coli. Seven people tested positive for E. Coli. Each of these seven
people was then matched with two healthy control subjects. The researchers compared the subjects
by giving them a survey about their recent exposures to a range of foods and environments.
Then they performed statistical analysis with the surveys and found that the unpasteurized
milk was the only item on the survey that was significantly associated to the illness.
Further investigation of the farm revealed the presence of biofilm, or living gunk, in
the milk holding tank and lack of good hygiene from the workers. From these findings, the
researchers concluded the unpasteurized milk was contaminated and led to the E.Coli outbreak.
Some people are still drinking unpasteurized milk because they think it is more nutritious.
They believe the heat kills beneficial nutrients along with the bad bacteria, but there is
a troubling lack of scientific studies to back them up. In fact, a research review conducted
by Jeffrey Lejeune and Paivi Rajala-Schultz looked at the results from twelve different
research experiments and concluded that only trace amounts of nutrients such as lactose
and vitamins are lost during the process of pasteurization.
Knowing all this information, everyone should choose pasteurized milk.