Native holly can provide caffeinated, antioxidant-rich beverage, UF experts say
GAINESVILLE, Fla. — Coffee and tea drinkers, take note — a University of Florida study says a beverage made from a native holly tree might be just the thing to give you a caffeinated kick-start, plus a dose of antioxidants.
Yaupon (YO-ponn) holly is the only U.S. plant that produces substantial amounts of caffeine, said Jack Putz, a botany professor affiliated with UF’s Institute of Food and Agricultural Sciences. A popular ornamental species, yaupon grows wild throughout the Southeast and can be grown in most coastal states.
Centuries ago, American Indians and Spanish settlers steeped yaupon leaves and twigs in hot water to make a stimulating beverage, but that use of the plant is virtually unknown today.
The resulting brew is dark brown and tastes much like green tea. If it makes a comeback, yaupon may spawn a cottage beverage industry, Putz said. And the antioxidants might be useful in nutritional supplements.
“A few years ago we were contacted from a pharmaceutical company in Texas,” he said. “At first, we thought their interest was in caffeine but they said that with all the decaffeinated beverages around, caffeine is cheap. What they were interested in was the antioxidants.”
Nitrogen fertilizer can boost yaupon production and caffeine content, according to a paper Putz co-wrote, published in this month’s issue of the journal Economic Botany. Nitrogen had little effect on antioxidant content.
The researchers focused on a popular ornamental yaupon variety called Nana, said Matt Palumbo, a botany master’s graduate and co-author of the paper. After receiving nitrogen fertilizer, Nana plants yielded 35 percent more leaves; caffeine concentration in the leaves shot up 265 percent.
Nana had about half the antioxidant content of green tea, he said.
“I have found genotypes with antioxidant concentrations at least as high as green tea,” Palumbo said.
Similarly, Nana’s caffeine content was low compared with concentrations reported in previous studies, he said.
Dry, unprocessed yaupon leaves contain between .65 percent and .85 percent caffeine by weight. Coffee beans are about 1.1 percent caffeine by weight and tea leaves about 3.5 percent caffeine.
More research is needed to learn which yaupon varieties have the greatest caffeine and antioxidant content, Palumbo said. Afterward, new cultivars can be developed.
One point seems clear — if U.S. residents begin drinking yaupon tea it could reduce demand for coffee, which may ease ecological pressure on coffee-farming regions of South America, Africa and Southeast Asia, he said.
It’s uncertain whether large-scale yaupon farming would be economically feasible in the U.S., but the antioxidants appear to have commercial potential, he said. And home gardeners might enjoy growing and using yaupon.
One caveat — before making yaupon tea it’s critical to obtain the correct plant, Putz says. There are numerous U.S. holly species, many of them not safe for consumption.
The taste of yaupon tea will be the make-or-break factor for potential users, says Dan Austin, an ethnobotanist based at the Arizona-Sonora Desert Museum in Tucson.
If they don’t like the flavor — something Austin says is quite possible — then they’re unlikely to drink the beverage regardless of the health benefits.
Still, he says, “if the proper spin is put on it, the potential is there.”