Milk Shelf Life Could Soon Become as Long as 60 Days
And not just because of better sniff tests
Good news for people who live in perpetual fear of their milk going bad: Scientists at Purdue University and the University of Tennessee announced earlier this week that they have created a new way to improve milk shelf life without chemical additives or preservatives. Researchers claim that their new pasteurization process can keep milk from spoiling for over 60 days, a vast improvement over existing practices which get two or three weeks of freshness from a carton of milk. And, of course, this goes well beyond you opening a carton, smelling it, and praying that curdled milk doesn’t come out onto your cereal.
The secret lies in a “rapid, low-temperature process” that raises the temperature of milk by ten degrees for less than a second. This process kills 99 percent of the microorganisms present in milk, increasing its shelf life dramatically. Pasteurization, the typical process for killing bacteria in milk and other foods, relies on heating milk to anywhere from 145 to 161 degrees Fahrenheit, depending on the procedure. But this process allows for a significantly larger number of bacteria to survive after heating, which results in milk’s shelf life being around two to three weeks.
For this experiment, scientists introduced Lactobacillus and Pseudomonas—two common bacterias found in milk—into a batch of pasteurized moo juice. They then pushed tiny milk droplets into a heated, pressurized chamber while quickly raising and lowering the temperature. At its hottest, the milk still never neared pasteurization temperatures, but was still able to kill of most bacteria due to the sudden temperature changes.
Bruce Applegate, Associate Professor at Purdue University’s Department of Food Science, said, “With the treatment, you’re taking out almost everything. Whatever does survive is at such a low level that it takes much longer for it to multiply to a point at which it damages the quality of the milk.”
And although the research appears promising, don’t expect milk shelf life to change quite yet while you’re digging for the freshest carton in the dairy aisle. Researchers caution that the technology isn’t quite ready for full adoption. So far, only one dairy farm in Ohio has implemented the process, and it still doesn’t tout the extended shelf life in its labeling. But either way, the technology could help reduce waste and allow milk to travel to more far-flung locales, which would normally suffer from shorter shelf life times by way of pasteurization. Whether or not this means you’ll remember to clean out your fridge before it starts to smell funky, however, is up to you.