Research aims to improve donor milk with advanced pasteurization

Human milk is widely seen as the best food for infants, especially for those born early. It contains important nutrients that help them grow, develop their brains and protect them from illnesses.

At the Rogers Hixon Ontario Human Milk Bank, donated milk is combined and heated to a safe temperature. This process, called Holder pasteurization, helps make the milk safe for very small and vulnerable babies.

Pasteurization helps preserve many infection-fighting components. However, it can also change some important nutrients and proteins, which may make the milk harder for babies to digest. Researchers are partnering with the Milk Bank to test a new method, called high-pressure processing, to keep donor human milk safe. This new method may help more babies get the benefits of donor milk compared to the standard process.

Dr. Michael Pitino has a PhD in nutritional sciences from the University of Toronto. He is working with the Milk Bank to study how different processing methods affect how proteins are digested. He is comparing high-pressure processing with a method called Holder pasteurization. To support this research, he created a model that simulates a preterm infant’s digestive system.

In high-pressure processing, donor milk is packaged in flexible containers and then placed in a specialized chamber. This chamber applies very high pressure, about five times the pressure found at the bottom of the ocean.

Research shows that high-pressure processing is comparable to Holder pasteurization in removing harmful germs. The method kills bacteria and viruses that can be dangerous for preterm babies. This method is already used in the food industry for products like cold-pressed fruit juices, which can’t be heated to kill germs.

The team found that important immune-related proteins in human milk, like lactoferrin, were more resistant to digestion with high-pressure processing than after Holder pasteurization. This is encouraging because lactoferrin is important to babies’ health. It not only helps their immune systems but also helps fight infections and supports brain health.

“This is an exciting finding, given that preterm infants are susceptible to various infections. Having donor milk with these antibacterial and antiviral proteins resistant to digestion may improve the ability of these infants to resist infection,” says Dr. Pitino.

The results show that high-pressure processing can be helpful, but more study is needed. With further work, researchers can learn more about the challenges of caring for babies in the Neonatal Intensive Care Unit (NICU). It’s essential to conduct more tests with patients before any changes are made at the Milk Bank.

“This preclinical work was important because we first needed to ensure that donor milk processed by high-pressure processing is safe for infant consumption, meaning that pathogens are destroyed, and that it has the potential to yield positive benefits to infants once digested,” explains Dr. Pitino. “The next step is to study this in preterm infants.”

(Update: Dr. Pitino and his colleagues have since published a related study External Link on how high-pressure processing affects the benefits of donor human milk for preterm infants.)

Access to human milk is very important for babies in the NICU. It helps them stay healthy and lowers the risk of serious health issues. This is especially true for preterm babies. Human milk can help prevent dangerous conditions like necrotizing enterocolitis (NEC), which affects the intestines.

Since 2013, the Rogers Hixon Ontario Human Milk Bank has helped babies who need extra care. The team collects donated human milk, pasteurizes it to make it safe, and distributes it to hospitals for babies in NICUs across Ontario and the East Coast.