Leave It to an Egghead to Crack This Case
Joe MacNeil tried just about everything: He pounded them, he ground them, he tried acid, bases and sandpaper. Still, the Penn State researcher could not solve the conundrum facing America’s egg processors: How do you get that thin membrane off broken eggshells?
Sound like one of higher education’s meaningless hypotheticals? Think again.
MacNeil finally has separated the shell from the membrane--and, in the process, he has created two lucrative products. His solution could be worth . . . who knows? A whole lot of money.
“When you find a solution for this kind of problem . . . these things are worth money,” MacNeil said recently, grinning from ear to ear. “That’s the American way!”
The problem is simple. Four of 10 eggs produced in this country are cracked open by commercial producers. The whites and yolks are sold by the gallon to bakeries, hotels, fast-food outfits and companies selling everything from cake mixes to mayonnaise to shampoo.
Every year, processors break 50 million cases of eggs--that’s 18 billion eggs--and get rid of 120,000 tons of shells.
With the membrane attached, the shells are worth $20 a ton for chicken feed or maybe fertilizer. Most of the shells just take up space in landfills. Hauling it away costs money, about $100,000 annually.
But scraping the membrane off the shell changes everything.
Egg shells are almost entirely calcium carbonate, which can be used in vitamin supplements, in toothpaste, in chemicals and as a pulp substitute by the paper industry.
More valuable is the membrane, which includes collagen, a protein used in a wide variety of medical products.
Egg-processing companies would not just save money; they’d make more of it.
The eggshells might be worth $200 a ton. Pure collagen, used by researchers in the process of growing cells, can go for $1,000 per gram, though the chicken variety would be worth much less.
Cutler Egg Products Inc. in Philadelphia has licensed MacNeil’s research from Penn State. The family-owned company is studying how to process and market the shells and membranes.
“It’s a big undertaking and no one’s ever done it before,” said Joel Cutler, chief executive officer. “It’s got huge potential.”
Collagenesis Inc. in Beverly, Mass., is one interested party. The fast-growing biochemical firm is researching ways the chicken collagen can be used in health care.
The membranes include the unusual Type 10 collagen, which prevents calcification. It could be used to make transplanted heart valves last longer and to treat osteoporosis. Egg membranes also contain the common Type 1 collagen, which could be used in cosmetics, plastic surgery and in sponges or powders as hemostats--used in hospitals to stop bleeding.
“We’re trying to decide what we can do with it,” said Dale DeVore, chief scientific officer for Collagenesis.
MacNeil and Penn State await approval of a patent on the deceivingly simple process to efficiently pull off the stubborn membranes.
“When I say they’re stuck together, I mean they’re stuck together,” said MacNeil, 67, a professor emeritus of food science. “I did every conceivable thing you could do and I couldn’t unstick that thing.”
MacNeil spent years looking at every attempt under a microscope in frustration--wishing he could just use a knife. Then he thought, why not use thousands of knives?
Meat processors use a device called a comitrol, a cylinder that looks a little like an oil filter. On the inside are razor-sharp blades. MacNeil’s procedure involves shooting the egg shells through the comitrol, producing a fluffy substance. When that’s dumped in water, the shells fall to the bottom and the membranes float to the top.
“You’re solving an environmental problem as well as getting a profit,” said Bernard Wentworth, a professor of poultry science at the University of Wisconsin at Madison, who was not involved in the research. “It makes sense.”
