The chocolate bug

Its beans are valued all over the world, but the cacao tree grows in very few places. The plant's survival depends on a tiny insect that is finicky about where it lives.

Jim Walsh, on his knees in a pile of rotting vegetation, is admiring a big, red fruit pod that protrudes from the trunk of a very healthy-looking cacao tree. Walsh (who is no relation to me) is the father of the fledgling Hawaiian chocolate industry, and he is very fond of this particular cacao plantation high in the mountains above the Kona coast of the Big Island of Hawaii.

The ten- to fifteen-foot-high cacao trees look like shrubs beside the towering macadamia nut trees in the adjacent orchard. The Hodge's Estate, as this plantation is known, used to grow only coffee and macadamia nuts. Now it also produces Walsh's most prized chocolate. Walsh's Hawaiian Vintage Chocolate Company sells chocolate by estate and year of vintage, like fine wine.

A light rain is falling and I can't help thinking that the place looks a mess--I am standing ankle-deep in a pile of wet, decaying organic debris.

"Do cacao trees need this much mulch?" I ask diplomatically, after slipping on a pile of wet cacao leaves.

"No, but the midges love it," Walsh replies as he twists a fruit pod off the tree.

"Midges?" The connection between no-see-ums, the tiny flies that bite exposed human flesh on sandy beaches, and chocolate is completely lost on me.

"If there weren't any midges, there wouldn't be any chocolate," says Walsh with an enigmatic grin, tossing me the red cacao pod, which resembles a partly deflated football.

The cacao tree bears fruit that is also called cacao (pronounced ka-KOW). The seeds inside the fruit pods are the cacao beans from which chocolate is made. Midges, as it turns out, are the only known pollinators of cultivated cacao. And a dearth of midges is one of the biggest problems facing the world's chocolate producers.

"There are cacao plantations in Central. America that get only 400 pounds of fruit per acre compared to the 4,000 to 6,000 pounds an acre we get here in Hawaii," says Walsh. "All because they don't have as many midges as we do."

Jim Walsh takes back his shrunken football and breaks the cacao fruit in half. Inside, there is a loose sac of sticky, transparent fruit enclosing thirty or forty thick, black seeds. Walsh encourages me to eat a little of the gooey fruit. Although it has a faint aroma of chocolate, the mucilaginous cacao flesh actually tastes more like lemon Jell-O. Walsh eats a little bit of it himself.

"It tastes good, doesn't it? We're thinking of making it into some kind of soft drink," says Walsh. He tells me that cacao fruit has been used to make beverages in Latin America for centuries.

When cacao was first harvested by South American Indians thousands of years ago, the sweet, citrusy mucilage was what interested them. Their interest was shared by bats, rats, squirrels, and monkeys, which gnawed through the skin of the cacao fruit to eat the pulp. Both humans and animals discarded the bitter-tasting cacao beans, thus guaranteeing the tree's dispersal. Cacao fruit pods are cauliflorous; that is, they grow out of the tree's trunk and branches rather than from the branch tips. And no matter how ripe they become, they never fall from the tree, which means that cacao is completely dependent on animals to spread and propagate it.

The tropical humidity of the Amazon Basin will cause cacao beans to rot if they are left out in the sun. So the seductive flavor of chocolate was not fully appreciated until cacao was cultivated in the drier climates of Central America and Mexico, where the cacao beans could be easily dried. Just how cacao came to Central America and how the uses of the bean were first discovered is, alas, unknown.

We do know that in ancient Mesoamerica, chocolate culture reached its full flower. Chocolate was not only a luxurious beverage but also a sacramental drink and a form of currency. Powdery residues taken from ancient Mayan stirrup-handled jars unearthed by archeologists were found to contain cacao. The English (and Spanish) word chocolate comes from chocolatl, the name of an Aztec beverage made of cacao, chiles, and vanilla beans. There was plenty of gold and silver in preconquest Mexico, but neither was used as money Aztec traders paid their debts in cacao beans.

The drier climates of Mesoamerica made chocolate production practical and cacao beans valuable to the Maya and Aztecs, but it also made growing cacao fruit more difficult. The insects that pollinate cacao are scarce in dry environments. This is the paradox that still plagues chocolate producers the world over.

Soon after Jim Walsh started his chocolate operations in Hawaii, he was visited by a midge specialist. "Chocolate had never been grown commercially in Hawaii, and we had no idea if we had the right kinds of midges here," Walsh says. The man who came to investigate was Allen M. Young, curator of zoology at the Milwaukee Public Museum and the author of a comprehensive book on cacao, The Chocolate Tree (Smithsonian, 1994). Young has been studying insects of the tropical rain forest since 1968 and their relation to chocolate production since 1979. He was curious to see for himself whether the right pollinating insects for cacao would be found in Hawaii.