Shelf-Stable (Aseptic) Milk: Everything You Need to Know

Have you seen milk on shelves that is not being refrigerated? Or heard that some of the milk you can buy in the dairy case does not have to stay in the fridge until after you open it? Wondering what makes this possible? We reached out to several team members and checked the Tetra Pak website to get you answers about aseptic milk, so you can enjoy the convenience this modern processing method offers.

How can milk be shelf-stable? What do they do to the milk?

Milk is made shelf-stable (refrigeration not required for storage) by pasteurizing it at a higher temperature. Which is called ultra-high temperature pasteurization, or UHT pasteurization. Traditional milk is heated up to at least 161 degrees for 15 seconds to kill harmful bacteria in the milk. With UHT, it is heated up to 280 to 300 degrees for two to six seconds. Both methods of pasteurization ensure safety and freshness.

Another thing that makes aseptic milk last on the shelf involves the sterile packaging and sterile environment in which the packaging happens. First, the bottles are produced on site; they are then sterilized so that they are absolutely clean. Secondly, the milk packaged in those bottles is in a sterile environment so that no bacteria or pathogens can contaminate the product. The combination of UHT pasteurization and bottling sterilization ensures that the milk lasts up to six months on the shelf without refrigeration.

Is it still real milk?

Yes! The aseptic milk is made with the same delicious, fresh and high-quality milk from local dairy farms.

While pasteurization has helped provide safe, nutrient-rich milk for over 150 years, some people continue to believe that pasteurization negatively affects the nutritional profile of milk. That could not be further from the truth. In fact, there are no meaningful changes to the nutrient package of milk as a result of pasteurization. When it comes to milk’s nutrients, all of milk’s minerals remain after pasteurization; there is, however, one small change when it comes to vitamins. Raw milk contains a miniscule amount of vitamin C (3.7 milligrams per serving), which does not survive the pasteurization process. By comparison, orange juice contains about 84 milligrams of vitamin C per serving.

How long is this milk good once I open it?

Aseptic milk will stay good in your pantry for up to six months. However, once you open it, it must be refrigerated immediately. Aseptic milk is best enjoyed within seven days of opening.

The important thing to remember for making any milk last longer is to keep it refrigerated – don’t ever leave milk out on the counter and try to finish individual servings of milk within an hour of serving. For every hour that your (traditional or opened aseptic) milk is above 45 degrees, you’ll lose a day of life off the label. So, if it takes you an hour to get home after you leave the grocery store with a gallon of traditional milk and the milk’s temperature rises to 45 degrees, it will last one day short of the date listed for freshness.

Is aseptic milk good for the environment?

Dairy farmers work hard to be environmentally sound on the farm, and dairy processors try to continue that tradition at the plant too. Aseptic milk is being made in smaller packages to help prevent food waste. So, the last couple glasses of milk from the gallon no longer have to be wasted if the jug goes bad before you can finish it!

In addition, dairy farms are committed to producing the purest milk possible on the farm, which means that the processing plant gets a better product to start with and getting it ready for the consumer is easier.

If you have questions about your aseptic product, look for the 800 number on the package and call to ask! Manufacturers are the best source of information about their foods. Have you tried aseptic milk? Tell us about it below!

By Jennie McDowell

Jennie grew up on a farm in Wyoming and go her first horse at age 3. She has a background in restaurant management and business strategy consulting and loves helping grow Dairy MAX's business relationships. When she's not working, Jennie can be found putting together amazing Halloween displays for her front yard. Learn more about Jennie

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