How Milk Gets from the Cow to the Store
Although some dairies have their own unique methods of milk production, most dairies in the United States follow the eight-step process seen below. Those eight steps are (in order): grazing, harvesting, storing, transportation, lab testing, processing, packaging and selling.
Step 1 – Cows Grazing
Step 2 – Harvesting Milk
Hand milking a cow
A cow is ready to be milked when her udder is full. The farmer has some flexibility when making a schedule of cow milking times. Usually, cows are milked in the early morning and again in the late afternoon. It is possible to milk a cow by hand. However, milking a whole herd of cows twice a day in this manner would take a great deal of time and energy. Before the invention of milking machines, people milked their dairy cows by hand by squeezing gently on the cow’s teats using the thumb and forefinger. Some people continue to milk a little by hand today.
Machine milking a cow
Cows are normally milked at least 2 times per day. Milking time takes about 5 minutes per cow but depends on the type of machine and the amount of milk the cow is producing. Most dairies have enough machines to milk over 20 cows at one time, reducing the amount of time the cows wait to be milked. Milking machines mimic the action of a young calf by creating a pulsating vacuum around the teat, which causes the milk to be released from the udder.
Step 3 – Storing Milk
Milk storage vat
Step 4 – Transporting Milk
Milk transportation truck
Step 5 – Laboratory Testing
Milk testing in a laboratory
Step 6 – Processing Milk
Whole milk, once approved for use, is pumped into storage silos where it undergoes pasteurization, homogenization, and further processing.
Involves heating every particle of milk to a specific temperature for a specified period of time and cooling it again without allowing recontamination.
Involves pushing the raw milk through an atomizer to form tiny particles so that the fat is dispersed evenly throughout the milk, stopping the fat from floating to the top of the container.
Machine for filtering and further processing
Includes reducing the fat content by micro-filtration, increasing the storage life by ultra high temperature (UHT) treatment, and mixing or culturing milk for flavored and yogurt products.
Step 7 – Packaging Milk
Machine filling and packaging milk
Now the milk is ready to be packaged for delivery to the stores where it will be sold. The milk travels through pipes to the automatic packaging machines that fills and seals the milk into paper cartons or plastic jugs. As the containers move through the assembly line, a date is printed on each of them to show how long the milk will stay fresh.
Step 8 – Selling Milk
Milk shelf in a store
After packaging, the milk is finally ready for the customers, and it is stored in a big, refrigerated room until it is delivered to stores to be sold.
Child drinking milk