Does this milk smell bad? We’ve all asked that question if we are a day or more past the date marked on the container. But what if we could wait even several more weeks before having to ask that question? That’s what an associate professor from Purdue University has been looking into.
The professor, Bruce Applegate, and colleagues from Purdue and the University of Tennessee explored a technique that included rapid heating and cooling of milk — and in their data published in the journal SpringerPlus, they found that the levels of harmful bacteria were reduced.
“It’s an add-on to pasteurization, but it can add shelf life of up to five, six or seven weeks to cold milk,” Applegate said.
Pasteurization, which removes most harmful pathogens that can cause illness and eventually spoil dairy products, is considered a high-temperature, short-time method, Purdue said. It gives milk a shelf life of about two to three weeks. This new research (called low-temperature, short-time) was able to show that that by increasing the temperature of milk by 10 degrees for less than a second eliminates more than 99 percent of the bacteria left behind after pasteurization.
“With the treatment, you’re taking out almost everything,” Applegate said. “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.”
Phillip Myer, a Tennessee researcher and co-author of the report, said the promise of the technology is that it could reduce waste and allow milk to reach distant locations where transport times using only pasteurization would mean that milk would have a short shelf life upon arrival.
To delve deeper into the research, check out Purdue’s website here.