Milk Safety and Production
Farmers and processors work hard to make sure your milk is safe
The following addresses common concerns about milk and explains the process involved in making sure the milk you drink is safe from farm to fridge. We have also provided clarification about organic milk and guidance on raw milk products. The Dairy Alliance does not promote the consumption of raw milk and other unpasteurized milk products.
Homogenization is a process that gives milk its rich, white color and smooth texture. Milk that has not been homogenized contains a layer of cream that rises to the top of its container. Before the homogenization process was used, milk was shaken or mixed to achieve consistency. The homogenization process involves reducing the size of the fat globules into minuscule portions that are dispersed evenly throughout the milk. Homogenization usually is achieved by pumping milk through small filters under very high pressure.
Pasteurization and Raw Milk
Pasteurization is a process that kills harmful bacteria by heating milk to a specific temperature for a set period of time. The process of pasteurization typically involves heating raw milk to 161.5˚F for 15 seconds and then immediately cooling it.
“Ultra-pasteurization” is a process that heats milk at a higher temperature for a longer period of time in order to extend a product’s shelf life. It is utilized to create shelf-stable milk products.
Some people continue to believe that pasteurization harms milk and that raw milk is a safe and healthier alternative. Raw milk can harbor dangerous microorganisms, such as salmonella, E. coli, and listeria, which can pose serious health risks to you and your family. Outbreaks of tuberculosis have been traced back to the consumption of raw milk.
Here are some proven facts about raw milk and pasteurization:
- Raw milk DOES NOT kill dangerous pathogens by itself.
- Pasteurizing milk DOES NOT cause lactose intolerance and allergic reactions.
- Pasteurization DOES NOT affect the taste of milk.
- Pasteurization DOES NOT make it safe to leave milk unrefrigerated for an extended period of time, particularly after it has been opened.
- Pasteurization DOES kill harmful bacteria.
- Pasteurization DOES save lives.
Pasteurization has been recognized around the world as an essential tool to ensure milk safety. This protocol has been in effect for more than a century and is regulated by the USDA.
Because milk is a product that comes from a female animal, all milk naturally contains very small amounts of hormones. However, the human digestive system breaks down those hormones and they are rendered inactive in our bodies.
Some dairy farmers choose to use a synthetic hormone called rBST (recombinant bovine somatotropin), which helps to boost milk production in cows. The milk of cows treated with rBST does not differ in safety or nutrition than that of cows not treated with rBST. The safety of milk from cows treated with rBST has been affirmed and reaffirmed by leading health organizations, including the U.S. Food and Drug Administration, the National Institute of Medicine and the Food and Agricultural Organization of the United Nations.
Cow milking is a process that occurs on average two to three times every day. Cows’ udders are first cleaned then inserted into automated milking machines. These gentle, pulsating machines collect the cow’s milk in about 15 minutes. Milk is released at about 100˚F and once collected, flows through refrigerated pipes into a sanitized bulk tank, where it is quickly cooled to about 38˚F. To ensure purity and safety, a sanitary, refrigerated milk truck transports the cooled milk to a processing plant, where it is pasteurized and homogenized.
Organic Milk vs. Regular Milk
A common misconception is that organic milk is healthier than regular milk. In reality, there are no nutritional or health differences between organic and traditional milk.
In regards to milk safety, there is no difference between organic and conventional milk production. All milk commercially produced in the U.S. adheres to the same strict federal standards for quality, purity and sanitation.
Dairy farms selling milk using the “USDA organic” seal must adhere to the following criteria:
- Cows are exclusively given feed grown without the use of pesticides or commercial fertilizers.
- Cows are given periodic access to pasture.
- Cows are not treated with supplemental hormones.
- Cows have not been given certain medications to treat illness.
There is no scientific evidence concluding that organic dairy products are safer or healthier than conventional dairy products. Strict government standards ensure both conventional and organic milk are wholesome, safe and nutritious. The USDA conducts an extremely thorough Pesticide Data Program, which concludes that all residue detections within milk and cream are “much lower than established tolerances.”
Read more on the study of omega-3 fatty acids in regular milk vs organic milk.
During milk processing, all post-milking handling must maintain the milk’s nutritional value and prevent deterioration caused by numerous physical and biological factors. In addition, equipment on the farm must be maintained to government and industry standards to uphold milk safety.
Here’s a quick run-through of the process of milk processing:
- Cows are milked at least twice a day. The dairy milk is immediately cooled from 100˚F to about 38˚F then stored at the farm under refrigeration until picked up by insulated tanker trucks at least once every other day. When the dairy milk is pumped into the tanker, a sample is collected for later lab analysis.
- When the milk arrives at the milk plant, it is analyzed for temperature, total acidity, flavor, odor, tanker cleanliness and the absence of antibiotics. The butterfat (BF) and solids-not-fat (SNF) content of the milk is also analyzed (BF content accounts for several different types of milk and dairy products, including whole milk, 2%, 1%, nonfat, and “half and half”).
- BF, SNF and volume are used to determine the amount of money paid to the farmer. Once the load passes these receiving tests, it is pumped into large refrigerated storage silos at a milk processing plant.
- Within 72 hours of receipt, the milk is pasteurized to kill all pathogenic bacteria that may be present (some bacteria do not cause spoilage, but are actually added to milk or cream after pasteurization to make “cultured” products such as cheese, cottage cheese, yogurt, buttermilk, acidophilus milk and sour cream).
- A large centrifuge called a separator, spins the milk at 2,000 rotations per minute, separating the cream and skim portions of the milk. Blending the components in various proportions creates different milk products. Excess cream is used to make ice cream and butter.
- A homogenizer forces the milk under high pressure through a valve that breaks up the butterfat globules to such a size that they will not “coalesce,” or stick together (homogenization does not affect the nutrition or quality of the product; it is done entirely for aesthetic purposes and to prevent cream from rising to the top of milk).
- Liquid vitamins are added to fortify the milk, as vitamin quantities can be reduced by the heating process and the removal of butterfat (many states have standards that require the addition of milk solids, such as calcium, iron and protein).
Additional quality control tests are conducted before the milk is flavored (in the cases of chocolate, strawberry and other flavored milks), bottled and shipped to grocery stores in refrigerated trailers. Once at the store, the dairy milk is immediately placed into a cold storage room or refrigerated display case, ready to be enjoyed by you and your family.