It takes a few changes of clothes to climb Malaysian Borneo’s Mount Kinabalu. At its peak, stone slabs offer no shelter, and its 4,095m-high altitude brings more cold than you might expect in the heart of the tropics. Further down the mountain, a thick tree canopy provides shelter, but it is a cool, misty forest that drips. And at the base is the slightly too-warm embrace of tropical rainforest.

Pouches of sticky rice in dull, mottled wrappers aren’t the type of snack that catches attention.

Seemingly unfazed by the sticky humidity, market vendors in the city of Kota Kinabalu, from where most journeys up and down Mount Kinabalu start, sell a variety of local foods to hikers returning from the summit. Amid the sizzle and clatter of food stalls and the enticing aromas of buttered prawns and barbecued fish, pouches of sticky rice in dull, mottled wrappers aren’t the type of snack that catches attention.  

But this modest bite is something quite extraordinary. Made from coconut-scented sticky rice wrapped in the traps of a carnivorous plant, the snack can be found in several countries in Southeast Asia. But in Malaysian Borneo, that consumption of nasi pelut (white rice) in periuk kera (pitcher plant), also known as lemang periuk kera, is thriving.

Mount Kinabalu is one of the richest biodiversity hotspots in the world. It is packed with life in varied forms, including some animals and plants that don’t live in the wild anywhere else such as several species of carnivorous pitcher plant. These plants use a variety of techniques ‒ such as nectar, smells and colours ‒ to lure insects, and their traps deploy sheer drops, smooth surfaces that cannot be scaled or blockades of bristles to prevent their prey from escaping.

Pitcher plants often appear on tourist information leaflets as a symbol of Mount Kinabalu’s biodiversity, but in markets in Kota Kinabalu and across Malaysian Borneo, they are part of the rich culinary culture of Malaysia’s indigenous tribes.

Dr Rachel Schwallier, lecturer at Grand Valley State University Department of Biology in Michigan, was in Borneo in 2012-2013 conducting research on the evolution and diversity of pitcher plants. On hearing about the use of pitcher plants in local cuisine, she expanded her work and returned to look at the culture and heritage of edible pitcher plants.

Lemang periuk kera is recognised as a Malaysian heritage food that differs from other methods of cooking sticky rice because of the way the pitcher plant is used. To make the snack, pitchers are cleaned and filled with rice, packed upright into a steamer, covered with coconut milk and then steamed for an hour. Cooked in this way, the naturally glutinous texture of local sticky rice is transformed into tidy coconut-flavoured packages.

One person interviewed by Schwallier described eating it on a highland trek in Borneo. In the case of this meal, the landscape provided cooking vessels as well as fuel for the fire: their tribal guides collected pitchers, coated them in mud and placed them on the coals of a fire to cook the rice.

“I was lucky enough to cook the snack along with a tribal family in Borneo, too, and it seems that the rich flavour really comes from the coconut milk that the rice is steeped in, making it sweet and full of flavour,” Schwallier said.

At market stalls in Kota Kinabalu and throughout Borneo, vendors customise their own versions: a bit of pandan leaf adds fragrance, while peanut or fermented shrimp paste creates depth.

The flask-shaped pitcher plant (named for its unique shape that allows it to consume falling leaves) is ideal for holding rice, though the common swamp pitcher plant also does the trick. One way to tell one from the other is that lemang periuk kera made with the common swamp pitcher plant can be eaten whole because the plant makes more pliable and chewable pitchers. The flask-shaped plant has pitchers that are much more like cardboard ‒ harder to chew but easy to peel off the rice.

Sometimes, use of plants – such as the edible Curcuma candida, a flower native to Myanmar and Thailand – in cooking is restricted in order to conserve them. But pitcher plants aren’t at risk of extinction. Only the right pitcher is picked from a plant: it must be small (but not too small), not too old or brittle. The rest of the plant is left growing in the forest, continuing to produce more pitchers.

In describing being taken into the forest by a family who were harvesting pitchers near the village of Kampung Duyoh in southwestern Borneo, Schwallier said: “I literally could not take a single step without crunching the pitchers below my feet – that is how well they carpeted the forest floor.”

Preservation of traditional food enhances the link that people have with their natural environment.

Schwallier believes there is conservation value in the consumption of pitcher plants. “Preservation of traditional food enhances the link that people have with their natural environment and sustainable forest practices,” she said. “Maintaining [this] connection… strengthens the value placed on local forests, which strengthens the likelihood that communities will call for preservation of their forest when it is threatened by drivers of deforestation.”

In line with conservation approaches that seek to maintain traditional plant uses, visitors to Malaysian Borneo can enjoy the taste of a food that tells a tale of people living in some of the richest forest in the world. And for hikers descending on market stalls in Kota Kinabalu, a bite of unassuming lemang periuk kera is a tasty reminder of their trek through the forest and the exotic plants that live in it.

Culinary Roots is a series from BBC Travel connecting to the rare and local foods woven into a place’s heritage.

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