They did what to your milk?

What exactly is done to milk after it reaches the processing plant, and why do they do it?

They did what to your milk?

“Well, you know what they do to the milk sold in stores!” That was the comment that I overheard recently. Being involved in the dairy industry since a young age, it peaks my interest to hear what people think is done to their milk in processing. Now, as an educator with Michigan State University Extension, I know that it matters what people think because it says a lot about how confident they are in our farmers, the food supply, and our regulatory system. 

So what exactly is done to milk, and why do they do it? There are five major things that are done to milk after it reaches the processing plant from the dairy farm. 

First, milk goes through a series of quality test and to ensure that no antibiotics are present. Antibiotics are used on farms to treat animals that are sick, much like you would get antibiotics when you are sick. Milk processors test for antibiotics so that they do not end up in milk in the stores. Farmers and processors do not add any hormones or antibiotics into the milk. 

Second, milk is standardized and separated. Milk is standardized into skim, 1 percent, 2 percent, whole, etc. through standardizers and separators. Excess fat from these processes is used in cream, ice cream, butter, dry milk, and other products. 

Third, the milk is pasteurized. The process of pasteurizing milk was first suggested in 1886, 24 years after Louis Pasteur developed this process of heating consumable liquids to reduce bacterial pathogens. In other words, it’s been around for awhile! 

Reducing pathogens was, and is, an important goal when we are trying to provide a high quality product like milk. A quote from Purdue’s Raw Milk FAQ indicates “No single process has done more to prevent tuberculosis and brucellosis transmission in humans, and pasteurization remains an effective method to reduce the risk of foodborne illness from dairy products”. Are we still at risk today if we drink unpasteurized milk? You bet, and research shows that the risk of contracting a number of possible foodborne illnesses is significantly higher for those that drink raw milk versus pasteurized milk. Individuals against pasteurization minimize these risks and worry about how milk may be altered by pasteurization. Indeed milk is altered, as heat can begin to change protein molecules (this is necessary to inactivate harmful bacteria), but research has proven that pasteurization does not degrade the healthful benefits of milk. One of the best papers that I have read on raw milk was produced by Purdue University, Mike Schutz and Mike Ferree, it can easily be found online

Fourth, milk is usually homogenized. Homogenization is the process of forcing milk at high pressure through small holes to break up fat globules so that the fat is evenly dispersed in the milk and does not separate and rise to the top. The history behind homogenization takes me to my alma mater, Michigan State University. Professor G. Malcolm Trout was credited with helping to make homogenized milk feasible in the early 1930’s. Non-homogenized milk is available from some bottlers for those who prefer the flavor and the opportunity to shake their milk before using it to disperse the cream. There are no health benefits or risks associated with homogenization. 

Fifth, some milk is fortified. Vitamins A and D may be added to milk. These vitamins are fat soluble vitamins, so milk makes an excellent delivery system for our bodies. 

Dairy farmers produce higher quality milk products than they have in the past, and Michigan producers are leading the way. Consumers can take confidence in our farmers, processors and regulatory systems that are bringing high quality food to their table.