Lush, densely forested Kerala, the exuberantly green south Indian state sometimes called “God’s own country”, is exactly the kind of place you would expect to produce a superfood. It just wouldn’t be the jackfruit.

Covered in spikes and emitting a stench of rotting onions, jackfruit can balloon to an ungainly 45kg, and its inside is coated in a thick gum that stains axes, machetes or whatever heavy-duty tool is employed to attack its leathery shell.

Yet thousands of miles from this tropical forest habitat, in food trucks in Los Angeles, vegan eateries in London – and now even at Pizza Hut– jackfruit consumption is surging among diners looking for an ethical alternative to meat.

In India, where the fruit originated, that demand is helping to drive a renaissance for a plant that only five years ago was still regarded as a backyard nuisance.

“They would fall from trees and rot, gathering flies,” said James Joseph, a jackfruit entrepreneur. “People would stack them outside their houses with a sign saying ‘Please take this away’.”

From a starting point of virtually zero, jackfruit exports, including to the US, Europe and Britain, grew to 500 tonnes last year, and could reach 800 tonnes by the end of 2019, according to Kerala’s agriculture minister, VS Sunil Kumar.

“The vegan trend in western countries will help [jackfruit farmers] tap a booming global market,” he said.

Jackfruit is renowned for its meaty texture but the cumbersome fruit comes in many guises, I learned in the hills around Kochi city, at the farm of VA Thomas, Kerala’s one-man jackfruit encyclopedia. “I’ve eaten a minimum of 3,000 varieties,” he declared “By taste alone I know each one.”

Jackfruit, or chakka in the local language, Malayalam, has flourished in Kerala for thousands of years. Even today, there are no jackfruit orchards in the state; trees grow wild on roadsides and in forests. For the past 25 years, Thomas has roved the state, trying to document every variety. “I taste it both green and ripe,” he said. His reputation is now such that people invite him to their properties, hoping he will include their jackfruit in a massive seed depository he is assembling. Nine in 10 samples are rejected. “Sometimes it can provoke an angry reaction,” he said.

Driving Thomas’s quest is a search for a particular kind of jackfruit – the one his mother would cook when he was a boy. “I have it in my mind from when I was aged seven,” he said. “I’m still looking for that old taste. I’ve come close, but not yet.”

Facebook Twitter Pinterest A ‘pulled pork’ burger made using jackfruit. Photograph: Westend61/Alamy

For lunch, Thomas served us dry jackfruit (chewy, tastes like honey), dehydrated jackfruit pieces (tasteless), fresh jackfruit (mutedly sweet) and boiled jackfruit mashed with turmeric and grated coconut (dense and savoury). He grinned widely as we ate. At 74 years old, with his glistening white teeth, shiny hair and smooth skin, he looked 15 years younger. I contemplated a second helping of the yellow mash.

Food researchers are trumpeting the potential for jackfruit to become a staple crop on a warming planet. “The thing about jackfruit is that it’s huge – one of the biggest tree fruits in the world,” said Danielle Nierenberg, president of the Food Tank, a Washington DC-based food study institute. “It’s large enough that families can eat one fruit for a long time. It takes relatively little care, doesn’t need a lot of irrigation and is resilient to pests and disease. So if we’re thinking of foods for the future, jackfruit is what we should be thinking about.”

But India is way behind in the race to cultivate the crop. Industries in China and Vietnam have been booming for nearly three decades. Around a third of the jackfruit that grows in Kerala is estimated still to be going to waste. The little progress that has been made is often credited to Shree Padre, a magazine editor who has turned his monthly farming journal into the fruit’s biggest cheerleader.

“Our magazine has come out with at least 32 cover stories about almost every jackfruit-growing country,” he said. “It was seen as the poor man’s fruit. Nobody was using it four years ago. Today, no fewer than 30 companies are making use of the jackfruit pulp alone.”

In May 2018, the Kerala government declared jackfruit the state’s official fruit, with the winning slogan: “Jackfruit is the best fruit. Its fruit has innumerable good qualities.” It is now being processed into ice-cream, crisps and juices. “We’ve opened a Pandora’s box,” says Padre. “With intense research, who knows what new things will come up?”

One of those leading that research is entrepreneur James Joseph. He is a former Microsoft executive but, like Thomas and Padre, has become an evangelist for the fruit.

“I can’t believe I am still doing this after five years,” he says, when I meet him at a hotel restaurant in Kochi. In 2014, he took leave from Microsoft for what was meant to be a brief experiment to see whether jackfruit could be turned into flour.

Facebook Twitter Pinterest A trader selling fresh jackfruit in Chennai. Photograph: Boaz Rottem/Alamy

Westerners mostly hail jackfruit for its ability to mimic pulled pork on tacos, or ham slices on a pizza. “That would be a crime to do in India,” Joseph says. “This is a country with a massive protein deficiency.”

Instead, he touts jackfruit’s potential to tackle a major public health crisis. Kerala is India’s best-educated state and one of its most prosperous. As it has grown richer, it has traded the diseases of scarcity for those of abundance: one in two households in the state include someone suffering from diabetes. Major culprits are the fistfuls of rice or oily flatbreads that accompany virtually every traditional meal, Joseph says.

“I realised that one cup of jackfruit has 40% less carbohydrate than a cup of rice, and four times the fibre,” he says. He signals for a waiter, who brings a plate of fish fried in batter made with one-quarter jackfruit flour. The main course is pizza, the base of which is also partly jackfruit flour. I can’t taste the fruit in either dish. “Exactly,” Joseph says excitedly. “You are eating a green fruit that behaves like bread.”

He is working with doctors to check out other health benefits. One paper he has co-authored with an oncologist, and which will be presented at a cancer conference in Spain in July, claims that a jackfruit diet can help to maintain white blood cell levels in people undergoing chemotherapy.

Another study, to be presented in Rome in April, claims the use of diabetes medication fell in Kerala during jackfruit season last year, when the government was heavily promoting the consumption of its new state fruit.

Joseph quit his job at Microsoft and now works in the jackfruit business full-time. “The company kept asking me to come back, but I said, look, I can’t stop this any more,” he says. “When you have something of this impact, you can’t stop it.”