—by K. C. Jaehnig, Media & Communication Resources, and Marilyn Davis, ed.

Could cheese cut your cancer risk? Could ice cream increase your chances of avoiding inflammatory disease? Could milk build a better brain? And could they do these things while saving the family dairy farm?

Amer AbuGhazaleh, an SIUC animal scientist, is trying to find out, with a three-year, $125,000 grant from the Illinois Council on Food and Agricultural Research (C-FAR).

That project is geared toward boosting the amounts in milk of two types of fatty acids believed to help protect against heart disease, cancer, and diabetes, among other ailments. One type, omega-3 fatty acids, comes primarily from fish oil and flaxseed oil. The second type, conjugated linoleic acid (CLA for short), is produced by bacteria active in the rumen, the first compartment of a cow's stomach. Cows produce only small amounts of CLA, however—not enough to give their milk an extra health punch.

During his doctoral research in South Dakota, where he worked with cows in confinement operations, AbuGhazaleh increased the amount of CLA and omega-3 fatty acids in their milk three- or fourfold when he added oils rich in those acids to their diet. But he thought he could do better.

So the first dietary change he made with one group of his Holsteins at SIUC was to turn the cows out to pasture rather than keeping them in the barn.

"Grazing has been shown to increase the concentration of [CLA] fourfold—we don't know why," he says.

He also began feeding those cows a mix of corn, soybean meal, vitamins, and minerals laced with a little fish oil and linseed oil.

"Not only does the linseed oil have omega-3 fatty acids, but it also acts as a precursor for the CLA, providing [material for the stomach bacteria to go to work on]," he says.

Combining the special feed with grazing caused CLA levels to increase a whopping tenfold and omega-3 fatty acids to increase fivefold compared with milk from cows not given the special diet, AbuGhazaleh found.

The dietary changes also cut the milk's saturated fat content in half—almost down to the content typical of 2-percent milk. "We're producing 2.5-percent milk right from the cow," he says with a grin.

He notes that enriched dairy products wouldn't be expected to be someone's only source of CLA and omega-3 fatty acids. But, he says, "If you replaced your 12-ounce can of Pepsi with the same amount of milk from our grazing study, you would get 278 milligrams of CLA and 135 milligrams of omega-3."

That could be a significant help to consumers trying to get the daily 650 milligrams of omega-3 fatty acids currently recommended by the National Institutes of Health. That amount equates to about three or four servings of fatty fish per week, AbuGhazaleh says.

While many small dairy farms already have turned to grazing as a cost-cutting measure, they are finding that even lower feed costs don't offset low prices for raw milk. AbuGhazaleh acknowledges that the special feed mix would be a little more expensive for farmers than the feed they typically use. But, he says, "our goal is to create a niche market" with increased revenues that would more than compensate for the extra cost. Many consumers are willing to pay a premium for omega-3 enriched eggs, he notes, and he expects that many would likewise pay a premium for enriched dairy products.

In fact, that's just what he found from a consumer survey conducted on campus earlier this year, where more than two-thirds of respondents said they'd be willing to pay between 10 and 20 percent more for enriched dairy products.

Most of that income could stay on the farm if farmers took advantage of newly available processing equipment, downsized to fit the needs of the smaller producer, to make cheese, ice cream, and pasteurized milk right at the dairy. To show it could be done, AbuGhazaleh spent a little less than $500 on equipment that allowed him to churn out those products in his lab.

He and his team made both enriched and nonenriched samples of these products, then served them up in a blind taste test to about 200 students and faculty. At least 60 percent said they liked the enriched products. (The figure is actually skewed to the low side, since some of the testers didn't care for dairy products in general but succumbed to the inducement of coupons for participating in the taste test.)

In addition to their herd of Holsteins, AbuGhazaleh and his students work with fermenters: custom-built contraptions of glass bottles, tubing, and controls set up to mimic what happens in the cow's rumen. Each bottle has a tube that conveys food into it, a tube that transports "saliva" to it to aid its digestion, and a tube that carries waste out of it and into a white plastic bucket.

These fermenters have certain advantages over live animals when it comes to AbuGhazaleh's research. "The biggest of these is cost," he says. "A cow has a 50-gallon stomach. It can eat 60 pounds of food a day, where the fermenter uses less than a quarter of a pound."

The fermenter experiments, part of a pilot study funded by an SIUC Faculty Seed Grant, are geared to look at what factors control the production of CLA in the rumen. "There are so many interactions in the cow's stomach—it's like a big puzzle," AbuGhazaleh says.

To follow the action, he adds molecule-sized markers to the fatty acid contained in the feed used for the fermenters. A type of oleic acid, it serves as a precursor for CLA production. The markers allow AbuGhazaleh to track what happens to the oleic acid in the digestive process—how microbes break it down and form intermediate compounds to eventually produce CLA.

"These markers are very expensive—between $1,000 and $5,000 per gram," AbuGhazaleh says. "One gram in a cow's stomach would be so diluted it would not work as a tracer, but the fermenter has a volume of less than a liter."

Understanding the complexities of how CLA is produced by the cow may enable him to take measures to further boost CLA levels. "We can experiment with certain conditions [in the fermenter studies], such as pH, food retention time, and different oil sources [in the feed]," he says. Those studies are ongoing.

AbuGhazaleh has his sights set on more than just milk, though. Next up: He and SIUC animal science professor Gary Apgar recently were awarded C-FAR funding through the College of Agriculture to see if tinkering with pigs' diets can increase omega-3 levels in pork. Stay tuned.