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CALS Food Scientist Puts The Squeeze On Whey For Valuable Proteins

Unique proteins hidden within whey help prevent ear infections in children, improve iron absorption in infants, boost the nutritional value of foods and bring more money to farmers and whey processors, says a University of Wisconsin-Madison researcher.

Mark Etzel, a food scientist and chemical engineer at the College of Agricultural and Life Sciences, recently applied for patents on a process to extract particular proteins with extraordinary health benefits from whey, the watery byproduct of cheesemaking. With this process, called ion exchange, Etzel can separate the proteins of whey more thoroughly than previously possible. By separating these individual proteins, processors can take advantage of their unique biological and physical functions. Etzel, working with the Wisconsin Center for Dairy Research, which partially funds his research, plans to build what he calls a “whey refinery” to separate and purify valuable whey components.

A whey refinery can be compared to an oil refinery that separates and purifies crude oil, converting it to usable value-added products like kerosene and gasoline, explains Etzel. “To me the dairy industry is where the crude oil industry was at the turn of the century,” he adds.

Etzel, who has a Ph.D. in chemical engineering, specializes in processing biological materials such as milk. His research focuses on finding ways to separate the unique proteins and minerals in whey. Unlike most plant proteins, milk proteins are complete. And because milk proteins come from mammals, they possess specific biological functions, says Etzel.

One example is lactoferrin, an iron-binding protein that Etzel has isolated from whey. Babies need iron for normal growth and development and according to the American Academy of Pediatrics, many infants don”t get enough. Lactoferrin grabs onto the iron in food, making more of the mineral available to the body, says Etzel. Adding lactoferrin to infant formula will help babies absorb more iron from their formula. But that”s not all. Lactoferrin enhances the body”s ability to fight infection, including viral infections, and shows antioxidant and anticancer effects, according to Rosemary L. Walzem, a registered dietitian, in an article she wrote about the health benefits of whey for the U.S. Dairy Export Council. It also protects the intestines from overgrowth of potentially harmful bacteria that need iron for growth, she adds.

Alpha-lactalbumin, a calcium-binding protein also isolated by Etzel, enhances calcium absorption and is one of the few proteins that remains clear when heated to pasteurization temperatures. Adding it to boxed juice could raise the nutritional value for children by supplying protein and calcium, says Etzel.

A third whey protein separated by Etzel”s ion exchange process is glycomacropeptide. In the United States, one in 10,000 babies is born with a genetic disorder called PKU. These babies cannot digest a particular amino acid (amino acids are the building blocks of protein). As a result, people with PKU follow a strict low-protein diet to avoid the offending amino acid. Glycomacropeptide is unique in that it happens to be missing this amino acid, making it a potentially rich source of protein for people with PKU, says Etzel.

Aside from their health benefits, whey proteins can generate economic benefits for producers and processors. When separated and purified, lactoferrin is worth about $136 to $180 per pound. Glycomacropeptide is worth a bit less at $32 per pound, but there is more of it than lactoferrin in whey, Etzel notes. Asked if the research is worth the cost, Etzel replied that “the increase in value you get is worth many times more than the increased cost of technology.”

Etzel worked with the Wisconsin Alumni Research Foundation on the patent applications. Believing that the rewards of patents should accrue to the University of Wisconsin, CALS biochemist Harry Steenbock established the Wisconsin Alumni Research Foundation in 1925. More than 3,000 discoveries have been disclosed to WARF. Based on these disclosures, WARF has obtained nearly a thousand patents and has granted the UW more than $316 million.