THE FRUIT DETECTIVE.

One hot summer day not long ago, just as the specialty food stores around town were putting up "First of the Season" signs to advertise their peaches, a rare and extraordinary shipment of apricots appeared in Manhattan. They were white apricots, which you almost never see in the United States. Unlike the familiar tawny-colored varieties, these had pale, almost translucent skin, with a yellow blush. And, unlike the cottony supermarket fruit, the white apricots tasted great: a rush of sugar, with a complex, slightly acidic aftertaste. The flesh almost melted in your mouth, and the juice was so plentiful that you had to bend over while eating one, to avoid staining your shirt.

The apricots were available at Citarella, which has four branches, and only at Citarella--a fact that pleased the store's produce manager, Gregg Mufson, a great deal. Like his competitors at the other high-end specialty stores around town, such as Eli's, Dean & DeLuca, and Grace's, Mufson tries to titillate his customers by giving them uncommon fruits--curiosities that they may have encountered in a restaurant, on their travels, or on the Food Network. "Anything new, anything different, and if I can get it directly from the grower it's even better, because there's no middleman," said Mufson, who is in his mid-thirties and wears a neatly trimmed goatee. "I want them to go 'Wow!' I want to blow their minds with something. They'll eat these apricots, and they won't forget that taste, and then they'll come back and buy some more of my fruit." Mufson pays attention to the food press, so that he can be sure to have the trendy fruits and vegetables in stock. "When the Times did an article on rambutans"--bright-red, golf-ball-size, tendril-covered fruits from Southeast Asia, with translucent, sweet-tart flesh--"we sold ten cases of them in a couple of days." Appearance, he added, is the most important quality in attracting people to new fruit--the more colorful the better--followed by sugar. "Basically, if it's sweet, people like it," he said.

At first, not many customers paid much attention to the new apricots. "That's a white apricot," one of the produce workers in the store said when a customer asked about the fruit. "First one I ever seen," he added. But the customer went for the Apriums--yellow-skinned, pink-fleshed plum-apricot hybrids, which have become popular in the past few years.

Soon, however, word about the white apricots got out. The pastry chef at Citarella thought they were one of the best fruits he'd ever tasted. The chef Daniel Boulud bought two cases of white apricots and was "crazy for them," Mufson said; Boulud used them to make apricot galettes. The owner of Citarella, Joe Gurrera, gave a white apricot to Martha Stewart when she came into the East Hampton branch of the store, and "she was blown away by it," Mufson reported. "Blown a-way." The store sold out of its supply in a couple of days; the next shipment disappeared even more rapidly. Mufson was delighted. "My boss gave me a compliment! My boss never gives me compliments. He said, 'This is the best fruit ever. We got to get more of this stuff.' All I can say is David really scored this time."

David is David Karp, a sometime "provisioner" for specialty stores like Citarella, and a noted fruit writer. He is the Fruit Detective, a persona he invented around the time he worked as a provisioner for Dean & DeLuca. His job is to range around the country and the world and find exotic fruits, or uncommon varieties of common fruits. In recent years, he has travelled to Madagascar to investigate vanilla, to Sicily to hunt for blood oranges, and to the Australian outback to research bush fruits. But most of his work is performed in California. The Fruit Detective is a familiar figure at the Santa Monica Farmers' Market--he's the one in the pith helmet with the leather chin strap, his fruit knife in a holster on his belt, looking like a slightly demented forest ranger as he interrogates farmers with rapid-fire questions and eats their fruit. Readers of Karp's articles, which appear regularly in the Los Angeles Times and Gourmet, follow him on his quest for pomelos, Asian pears, mulberries, and persimmons. Most people experience a truly great piece of fruit very rarely--that perfect peach you ate one summer day long ago, a taste you hope for in ...