By Sharon Omahen
University of Georgia

University of Georgia food scientists have found a way to increase a key cancer and heart disease preventative in peanuts to levels far higher than those in red wine.

Experts often tout the benefits of red wine as a source of resveratrol, an antioxidant proven to protect against cancer and cardiovascular disease.

"American diets are high-fat, and the incidence of heart disease is high in this country," said Anna Resurreccion, the UGA food scientist who led the project at the Food Innovation and Commercialization Center in Griffin, Ga.

The French Paradox

"The French eat high-fat diets, too, yet heart disease levels are low there," she said. "This is what's referred to as the French Paradox. They attribute their health to the red wine they drink."

The peanuts Resurreccion modifies in her lab have up to 12.3 times more resveratrol than red wine. "A study of 29 different wines showed an average of .6 micrograms per gram and, in exceptional cases, 5 micrograms per gram," she said. "Our resveratrol-enhanced peanuts have almost 8 micrograms per gram."

Having increased levels of resveratrol available in peanuts, she said, opens up avenues to many new products that can carry its "cancer chemopreventive and anticardiovascular-disease compounds" in meals and snacks.

Perfect for peanut lovers

"Young children can't very well drink wine," she said. "But most of them love peanut butter and peanut snack foods."

Peanuts with increased resveratrol will help Georgia peanut farmers and food manufacturers, too.

"This technology will help increase the number of product lines made using resveratrol-enhanced peanuts and will give the manufacturers a competitive advantage," Resurreccion said. "We used a runner variety of peanuts, so Georgia farmers will benefit as well."

Resurreccion is now partnering with Belle Plantations, Inc., of Georgia to use resveratrol-enhanced peanuts to commercially manufacture peanut flour.

Both the enhanced peanuts and their flour by-product will be used to make products like pasta, candy bars, snacks, cakes, breads, power shakes and other health drinks, she said. Peanut butter with increased resveratrol is another possible product.

Resurreccion and her UGA colleagues first thought of increasing peanut resveratrol levels after reading reports that boiled peanuts contained higher levels of the compound.

So how do they do it?

Stress is the key to the process

"The method involves slicing the peanut kernels into tiny pieces," Resurreccion said. "This causes the first stress. Then we apply an additional stress through ultrasound technology."

Because the nuts have to be sliced, the scientists haven't been able to increase the resveratrol levels in whole nuts.

So far, the only drawback to the project is a slight off-flavor detected in a peanut butter prototype by a consumer panel and verified by the university's trained taste panel.

"Overall, the consumer panel was receptive to the peanut butter product, but they did detect a slight difference in flavor," Resurreccion said. "Our UGA trained panel noted that it was not as roasted-peanutty tasting."

UGA has applied for a patent for the new process. Food scientists there are ready to fine-tune the process to get the highest resveratrol levels and best flavor possible.

For the past four years, Resurreccion and graduate student, Jamie Rudolf, have been developing the technology as part of a multiyear, $1 million U.S. Peanut Collaborative Research Support Program grant. The grant also resulted in the development of a chocolate peanut spread and a reduced-calorie, cracker-coated, peanut snack.

The project also led to Resurreccion's Vitamin-A fortified peanut butter, which is being commercially produced in the Philippines to alleviate deficiency symptoms, including blindness, in 35 percent of the children there.