A frenzy overtakes the teeming harbor here as a wooden-hulled riverboat chugs into port.
"It's here!" cries an expectant buyer, one of many shoving his way toward the craft in a sweaty mercantile crush. "The gold! The purple gold!"
The cargo is acai (pronounced ah-sigh-EE), the unassuming fruit of a jungle palm that has gone from Amazonian staple to global wonder-berry: a much-hyped ingredient in smoothies, sorbets, nutrition bars and countless trendy treats from L.A. to London to Tokyo.
Acai's cachet derives not only from the berry's antioxidant traits and supposed Viagra-like powers of vitality, but from its green pedigree: It has been acclaimed as a renewable resource that provides a sustainable livelihood for tens of thousands of subsistence harvesters without damaging the expanses of the Amazon. Because of acai, the jungle is more valuable standing than felled.
With acai a global sensation, however, some fear the berry's runaway success may spell trouble for the rain forest -- a prospect that dismays even the Southern California brothers who are credited with launching the craze in the U.S.
International conglomerates are elbowing their way into the acai trade, while traditional cultivators are intensifying production at the expense of other trees. Conservationists worry that acai could succumb to the destructive agribusiness model: clear-cut lands, sprawling plantations and liberal application of pesticides and fertilizer.
"There's a kind of 'green deforestation' to plant acai," says Alfredo Homma, agronomist with the Brazilian Company for Agricultural Research, a publicly funded institute. "They don't bring down all the trees and leave the area deforested. They bring down diverse forests and replace them with one single culture -- acai."
An everyday food
In the stifling Amazon delta, acai is less a hip superfood than a poor man's staple: Downtown Belem even features an acai drive-in.
Many people here eat acai every day, typically as an accompaniment to river fish or sprinkled with toasted cassava, a widely consumed tuber. Fresh acai, served at room temperature, is a tart, earthier version of the frozen, pasteurized and inevitably sweetened incarnation marketed abroad.
"It makes you grow," says Vital Vieira, who owns one of the many retail storefronts where acai berries are shelled, separating the large, inedible seed from the prized pulp and purple skin.
The slender acai palm typically thrives on the margins of the forest -- along rivers and streams, where some sunlight filters through the canopy. For generations, men such as Domingos Bravo Rosa have harvested the berry in the dense forests across the river from downtown Belem, a onetime rubber boomtown that is now the capital of the Amazonian state of Para.
"We don't destroy the forest," says Rosa, 44, a lifetime acai harvester like his father before him, as he maneuvers his boat to his home on nearby Combu island. Rosa knows where to find the acai; a single palm is often hidden among a score or more of other trees. He hires two harvesters, who must shimmy up and down palms sometimes 60 feet or more in height, a dangerous job.
"Acai has allowed my family to live well," he says. An electric generator powers a stereo and two TVs in his family's two homes. This is a rain-forest clan with five cellphones.
A different model of acai harvesting is found on neighboring Murutucu island. Here, Ben-Hur Borges, a forest engineer turned acai entrepreneur, proudly displays the 1,350 acres of elegant groves that supply his firm, Amazon Fruit, a major exporter of acai to the United States and Europe.
The rows of acai trees stand in sharp contrast to the occasional palms that Rosa and others seek out in the jungle. Here, small rail cars carry harvested acai on wooden tracks to Amazon Fruit's processing and freezing plant.
The sprawling plantation resembles the kind of acai "mono-culture" that is anathema to conservationists. But Borges argues that his success demonstrates how more than one version of acai production can thrive, with both environmental and social benefits. He says his hard work draining and reshaping the island brought back a "degraded" forest -- the fate of much of the Amazon, which has been ravaged by loggers, developers and cattle ranchers.
"When we got here, we found only riverside peoples living on an island where everything that could be reaped had already been taken away," says Borges, who began developing the island 13 years ago. "There was no acai, no timber, nothing. There were bushes and trees with no economic value. . . . We enriched and rebuilt the island, with an emphasis on acai.
"Acai," he concludes, "is the ideal native plant to help rebuild degraded forests."
Acai might not be such a global sensation today were it not for a pair of Southern California brothers, Ryan and Jeremy Black, who co-founded Sambazon, based in San Clemente. The company now boasts sales of $25 million a year in juices, powders and other acai products. But it all started with a surfing trip.
Ryan Black returned from a millennium-marking surfing visit to Brazil blown away by acai. In the 1990s, acai had spread from the Amazon to become a staple in surfer shacks, juice joints and weightlifting clubs along the heavily populated Brazilian coast. Now it's a common sight at major supermarkets and health food emporiums the world over. Among the retail chains selling acai products are Whole Foods Market, Vons, Albertsons, Gelson's Markets, Jamba Juice and Juice It Up.
This year, Black says, Sambazon plans to process 11,000 tons of acai from its Brazilian production base, making it the world's leading supplier.
All of it comes from individuals such as Rosa picking the fruit from wild acai palms, according to the Black brothers, who have won praise internationally as "green" business pioneers.
"The whole idea is to protect the biodiversity of the forest," Ryan Black says. "The idea is not to clear-cut everything on the land and plant acai trees."
But a growing concentration of acai plantings amid rising demand has Black worried about a "dangerous cycle": transformation of bio-diverse forests into proliferating stretches of acai palms. That means removing other tree species to make way for acai. His hope is that consumer preference for certified organic acai, picked in the wild, will help preserve the forest and support harvesting families.
"We want to look back [in] 20 years and see that acai has been a positive force in the Amazon," Black says, "not just a fruit that became domesticated and found success at the price of the local people and their environment."
Special correspondent Marcelo Soares in Sao Paulo, Brazil, contributed to this report.
Acai in Brazil
For a video of acai harvesting, sales and consumption in Brazil, go to latimes.com/acai.