Beyond the froth, cocoa teems with antioxidants that prevent cancer, Cornell University food scientists say. Comparing the chemical anti-cancer activity in beverages known to contain antioxidants, they have found that cocoa has nearly twice the antioxidants of red wine and up to three times those found in green tea.
Their finding will be published Dec. 3 in the American Chemical Society's Journal of Agriculture and Food Chemistry , a peer-reviewed publication.
Scientists have long known that cocoa contains antioxidants, but no one knew just how plentiful they were compared with those in red wine and green tea.
The Cornell researchers, led by Chang Y. (Cy) Lee, chairman of the Department of Food Science and Technology at the university's New York State Agricultural Experiment Station in Geneva, N.Y., say the reason that cocoa leads the other drinks is its high content of compounds called phenolic phytochemicals, or flavonoids, indicating the presence of known antioxidants that can stave off cancer, heart disease and other ailments. They discovered 611 milligrams of the phenolic compound gallic acid equivalents (GAE) and 564 milligrams of the flavonoid epicatechin equivalents (ECE) in a single serving of cocoa. Examining a glass of red wine, the researchers found 340 milligrams of GAE and 163 milligrams of ECE. In a cup of green tea, they found 165 milligrams of GAE and 47 milligrams of ECE.
"If I had made a prediction before conducting the tests, I would have picked green tea as having the most antioxidant activity," said Lee. "When we compared one serving of each beverage, the cocoa turned out to be the highest in antioxidant activity, and that was surprising to me."Phenolic compounds protect plants against insects and pathogens, and they remain active even after food processing. A decade ago "food scientists did not know that phenolics had an important role in human health," says Lee.
Lee and his colleagues used two chemical tests that measured how well the cocoa compounds scavenge for free radicals -- agents that cause cancer, heart disease and other diseases.
In the paper, the researchers discuss eating chocolate bars instead of drinking cocoa. "Although a bar of chocolate exhibits strong antioxidant activity, the health benefits are still controversial because of the saturated fats present," the researchers write. They explain that cocoa has about one-third of a gram of fat per one-cup serving, compared with eight grams of fat in a standard-size 40-gram chocolate bar.
Faced with the confusing prospect of drinking red wine or green tea or cocoa, Lee suggests enjoying all three in different parts of the day. "Personally, I would drink hot cocoa in the morning, green tea in the afternoon and a glass of red wine in the evening. That's a good combination," he says.
The research paper is titled "Cocoa Has More Phenolic Phytochemicals and a Higher Antioxidant Capacity than Teas and Red Wine." Lee's collaborators are his former graduate student, Ki Won Lee; Hyong Joo Lee, a professor at Seoul National University, South Korea; and Young Jun Kim, a post-doctoral researcher at Cornell. The research was funded in part by the BioGreen 21 Program, Rural Development Administration, Republic of South Korea.