A juicy business: UC Riverside's citrus center experiments with designer fruit
L.A. Times 2/15/07
There was the nurseryman from France who came to the United States only to admire its unusual and succulent fruit. A local restaurateur, looking for new flavors for his entrees, nibbled on a variety of citrus blossoms.
Then there was the obsessed tangerine fan — a gourmet grocer from Texas who wanted his picture taken next to the Seedless Kishu mandarin tree.
"That was a little strange," said Tracy Kahn, a UCR scientist who watches over the trees.
More than 1,000 members of the citrus family tree thrive in UCR's Citrus Experiment Station, which celebrated its 100th anniversary on Wednesday. Generations of researchers here have developed and bred dozens of unique tasty fruits.
UC scientists established the Citrus Experiment Station in 1907 as a research center to support Southern California's growing citrus industry and the center ultimately became the seedling from which UC Riverside sprouted in 1954.
Even with the mushrooming growth of new homes and shopping centers that now surrounds the university, UC Riverside's citrus groves remain among the most diverse in the world.
During tours — yes, the citrus station does draw in the curious — visitors learn that lemons weren't always small and cute. Long before grocers began stocking the fist-sized variety popular today, citrus growers fumbled with its ancestor, a lumpy 5-pound fruit the size of a Nerf football.
Growers in India are believed to have produced what is now considered the modern lemon about AD 100, after decades of crossing it with smaller citrus varieties.
In more modern times, UC Riverside scientists have developed some best-selling fruits, including the Oroblanco grapefruit-pummelo hybrid, with its surprisingly sweet taste, and the tangy Gold Nugget mandarin.
But many of the university's contributions have been more utilitarian, such as finding ways to eliminate bothersome bugs without pesticides.
The 400-acre station is now called the Citrus Research Center and Agricultural Experiment Station to reflect its expanded mission, which now includes research on asparagus and other vegetables.
A hundred years ago, orange groves blanketed much of Southern California, driving the station's establishment. But as citrus and other agriculture give way to development, the university has come up with creative ways to stay relevant as a state and worldwide resource.
The university runs a state-of-the-art bug lab, where entomologists are using genetics to combat the glassy-winged sharpshooter, responsible for transmitting Pierce's disease, which kills grapevines and threatens California wineries. The insect also carries bacteria that harm almond trees, citrus trees and alfalfa crops.
At the museum, a 25-acre parcel planted with the 1,000 citrus varieties — two trees of each — Kahn regularly entertains international citrus gurus and has become a sort of ambassador, once lugging 250 pounds of fruit to Washington to tantalize members of Congress during a conference on land-grant universities.
Kahn has also hosted local chefs using the groves for inspiration. The tiny caviar-like fruit of purple-skinned Australian Finger Limes makes a good garnish; the Buddha's Hand, a fingered citron that looks like a miniature yellow octopus, makes an unusual centerpiece.
Brein Clements, chef-owner of Restaurant Omakase, a new downtown Riverside eatery, came in search of an orange blossom to decorate his dishes.
"So we went around chomping flowers," Kahn said. Kahn assumed the sweetest fruit trees would have the best-tasting flowers.
"But it didn't work out that way. Some of those were pretty gross," she recalled.
Instead, Kahn introduced Clements to the Australian Finger Limes, which he purees into a sorbet. He took a few Rangpur mandarin-limes and reduced them into a syrup for scallops and beets.
The two exchange ideas every other week and are planning a citrus-themed benefit dinner in March to raise money for the museum.
As for flowers, Clements isn't giving up. He'll head back into the groves this spring when more trees will be in bloom. He has big plans for the blossoms, including their use in honey and mustard infusions and curing them with salt and then packing them around yellowfin tuna steaks.
"I don't even look at basic oranges and lemons when I go there," Clements said. "When you're there, you feel like you're taking a trip around the world. She's got stuff from Morocco in one row, then in another row she's got Spain and Egypt … stuff that no one else in the United States has."
Escorting visitors through the rows of trees, Kahn sometimes pulls out a knife and treats guests to tasty Moro blood oranges and seedless mandarins fresh off the tree. But visitors beware, one lick of another fruit — the citrange — leaves a taste you remember for a week, and not because it's sweet; it's more like sickly rotten.
The Texas grocer who wanted his picture taken next to the Seedless Kishu mandarin tree sampled other tangerines and oranges on the tour. Still, for him, none topped his tiny, fluffy-skinned favorite.
"I'm a big fan of the Kishu, it's one of my favorite things," said Lee Crenshaw, a produce buyer for Central Market, a gourmet grocery chain. The mandarins have a short season but are extremely popular with customers. For two weeks every January, the golf ball-sized fruits fly off the shelves, he said.
Despite the station's expanded goals, citrus breeders haven't let up on their quest to develop sweeter, hardier fruit. The university released three more seedless tangerine varieties to growers in 2002: Shasta Gold, Tahoe Gold and Yosemite Gold. The first commercial crop should hit grocery stores in two years.
Meanwhile, the newly released Tango tangerine could become one of the most widely grown.
Unlike other varieties, Tango trees don't have to be grown in isolation to be seedless.
It takes about 20 years to develop a new variety, said Mikeal Roose, UC Riverside's citrus breeder and professor of genetics. For every marketable fruit sent on to growers, there are 50 others that don't make the cut, he said.
Roose said that he tastes so many contenders that his dentist gives him a special treatment to protect the enamel on his teeth.
Roose and his team of researchers still use some age-old techniques to create new fruits, combining pollen from one tree with the flowers from another and harvesting seeds from the resulting fruit.
But some of the work has gone high-tech. To produce the Tango variety, researchers blasted baby trees known as budsports with X-rays to spur mutations. And by mapping the citrus genome, researchers can determine early on which seedlings deserve planting.
As UCR moves ahead with plans for new medical and business schools, the citrus station will lose a few rows of trees. But perhaps more worrisome for the agricultural school is a problem facing the industry at large.
"We're all talking about how we can get undergrads interested in the agricultural sciences. Should we call it something different than 'plant sciences?' " said Donald Cooksey, dean of UCR's College of Natural and Agricultural Sciences.
"It's something we're still working on," he said.