From "Moo" to You: How Milk is Made.
1: Have you "herd" the one about…
The fresh milk and other dairy products you enjoy every day start on a dairy farm right
here in the Midwest, not too far from where you live and buy groceries. Midwest dairy
producers each have a herd of dairy cows on their farms — some have just a few
dozen cows and some have very large herds of 100 or more.
These dairy cows are fed healthy and nutritious diets so they will make lots of fresh
milk every day. Dairy cows also receive attentive care by the farmers and local
veterinarians to make sure the cows are always in the peak of health.
By and large, a dairy cow's typical day includes 8 hours of eating, 8 hours of sleeping,
and 8 hours of chewing cud (something that all bovine animals do because they have two
stomachs and… well, that's another story!).
2: It's not parlor tricks, but it is kind of magic.
Twice a day around 5 a.m. and 5 p.m. (sometimes 3 times a day), the dairy cows are
brought to the "milking parlor," a large room outfitted with stalls and special milking
equipment. Dairy cows are rarely milked by hand anymore because that would take too long
and today's modern milking systems are far gentler, more efficient and productive.
In the milking parlor, the cow's udder is carefully cleaned, then the milking equipment
is attached and turned on. It can take about 10 minutes or so to milk one cow and
afterward, the cows feel much better because at 8.6 lbs a gallon, milk is pretty heavy
for them to be carrying around all day! It's not uncommon for a dairy cow to produce
60 lbs., 70 lbs. or more per day! After milking, the cows are again cleaned and sent out
to pasture.
3: Fresh milk is "in the house!"
The milking equipment pumps the fresh milk from the cows along stainless steel pipes to
another room called the "milk house." In this room is a large stainless steel tank that
chills the new milk to 38° F or less. The tank constantly agitates the milk to make
sure its temperature is consistent throughout, and to prevent the cream and milk from
separating. After every milking session, the stainless steel pipes from the milkers to
the tank are thoroughly cleaned by automated equipment.
The milk house tank stores the chilled fresh milk until the milk truck arrives. After
every pickup, the tank, like the pipes, is cleaned.
4: Milk trucks are cool, really!
Every 24 to 48 hours a large, shiny milk truck comes to the dairy farms to collect the farmers' milk. These stainless steel tanks on wheels hold up to 5,300 gallons and are heavily insulated to keep the milk chilled for the trip to the processing plant. These trucks are licensed by the state and inspected regularly for maximum cleanliness.
5: Excuse me, I need to take your temperature.
As soon as each tanker arrives at the milk plant, samples are drawn from the milk inside. One is immediately checked for temperature. If the temperature of the milk has risen beyond 44° F, the entire load is discarded. No exceptions!
6: Making the grade means passing the test.
Another sample goes to the lab to check for bacteria. No milk is ever unloaded without passing this test. Within a matter of minutes the results are received and if the milk passes the test the pumping can begin. After unloading, the tanker trailers are then thoroughly cleaned and made ready for the next trip.
7: See you later, cream.
Inside, the milk is run through separators to remove the cream. The skim milk that
remains flows on. Some will remain skim and later some will have the cream returned to
it, in varying proportions, to create 1%, 2%, whole milk, buttermilk, half and half and
flavored milks. The rest of the cream will flow on to other tanks for use in making ice
cream and other products.
In these mixing tanks, other ingredients are added to make flavored milk like chocolate,
strawberry or eggnog.
8: Takes a heatin' to pasteurize, takes a beatin' to homogenize!
In the pasteurization process, the milk is heated to over 160° F, kept there for 15
seconds and then rapidly cooled to 35° F. This eliminates any microorganisms that
could cause diseases or accelerate spoilage.
The homogenizing tank makes the milk consistently smooth. Under lots of pressure, it
whips any butterfat into very tiny particles that are too small to separate from the milk.
9: Thar she blows!
Many processing plants have equipment to "blow mold" their own plastic milk bottles.
Plastic pellets are heated to over 300 degrees. Then, "blow mold" machines create molten
plastic "balloons" that are encased by the two halves of the mold. After a few seconds of
pressure, out comes a gallon plastic jug! Another machine trims all the excess from the
container and then sends that scrap material around to be re-used by combining it with
the raw material pellets.
The half-gallon jugs come out of the molds a little larger than they should be. So, they
are sent through an "annealer" where they are briefly subjected to 1100-degree heat.
That's enough to shrink them to the proper size.
Overhead conveyor systems move the containers along to the next step in the process.
10: Go ahead, label me fresh.
In a continuous automated process, the correct labels are applied to the gallon or
half-gallon bottles (or the many different package sizes offered).
This area is also where paper cartons are folded and ready to be filled.
11: Who, what, when, where and whey.
The last step in packaging production is to pass by the video jet sprayer. Here, in the blink of an eye, important information is sprayed on each jug, bottle and carton by an ink jet. This information includes the freshness date, the code for the specific milk product and the initials of the operator.
12: Fill 'er up with the good stuff
Automated conveyors route the packages to automated filler machines that precisely fill the bottle or carton and even puts on the cap and/or seals the paper cartons.
13: Coming to a supermarket near you.
From here the milk is packed into crates and moved to cold storage. These rooms are often as big as a dozen residential homes and they are refrigerated to 38° F. The people who work in these rooms dress as if it was winter, even in the middle of July! Milk remains here for no more than a day before it is trucked to your local supermarket or convenience store.
14: Sure, have another glass!
The milk and other dairy products you buy at your favorite store are delicious and nutritious because freshness and great taste have been carefully maintained every step of the way…from "moo" to you!