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Lemon Myrtle
The Next "Best Thing"
By Allen Kinast

Talk to people who have discovered lemon myrtle, and you'd think there was a write-in campaign to get rid of "sliced bread" as the next best thing. Pharmaceutical wonder tree of the rainforest, they say. A taste more lemony than lemon, they contend. A possible cure to a Pandora's box of ills, they assert.
In today's media-saturated world, where most "new things" are passé before we ever learn about them, it's kind of exciting to come across something that's truly new. And when you look at the facts surrounding lemon myrtle-that the first commercial farm is only five years old, and the first bulk shipments to the United States arrived just three years ago-it's hard to resist calling this a legitimate discovery.

Tart Beginnings
Lemon myrtle was briefly noted in the journals of Baron von Mueller, a prominent German-Australian botanist, who served as an expedition botanist on a tour along Australia's northern coast in 1858. Mueller gave the citrus-smelling tree its botanical name, Backhousia citriodora, in honor of another Australian botanist, James Backhouse, who had performed some of the first botanical studies of the Queensland rainforests in the 1830s.
While the baron had earned an international reputation for recognizing the hidden commercial value of plants and trees, his Backhousia citriodora initially received only scant attention. Some 50 years later, a German pharmaceutical company got around to analyzing the tree's leaves and noted a "high citral count" of 90 to 97 percent. While the beginning of the 1900s saw some limited harvesting of the wild trees for essential oil production, lemon myrtle stayed in the relative shadows of obscurity.
Curiously, there is no recorded use of the plant by the aboriginal natives of Australia. Lemon myrtle was never abundant even in the primordial rainforest; its scarcity meant that only a few local tribes were even aware of its existence.
When a shortage of lemon essence during World War II threatened the manufacture of soft drinks for the more than one million American GIs on leave in Australia, lemon myrtle was quickly pressed into service. While the tree's leaves undoubtedly did an excellent job quenching the thirst of the boys away from home, most of the rainforest's stock of lemon myrtle was felled in the process, and the tree became endangered. Some limited essential oil production continued in the region in the 1950s, but by this time the tree's genetic lineage had dwindled considerably, and by the late '80s early '90s, the tree was listed as a "rare" species.
Attempts to revive lemon myrtle cultivation went nowhere until 1995, when research scientist Brian Milgate and natural therapist Cass Betts discovered one of the largest concentrations of wild lemon myrtle known. Their find, in the Conway range in the Whitsundays Queensland, was important for its density of lemon myrtle trees and because the percentage of citral found in the leaves was some of the highest ever identified.
Still, finding good genetic stock was only half the challenge, for as Milgate points out, "while lemon myrtle's potential had been identified for more than 100 years, nobody was able to grow it commercially." Milgate and Betts spent two years developing systems for growing the tree that were commercially viable and environmentally sustainable. They acquired land in the same area as their discovery, planted selected cultivars of the species and set about developing a full-scale lemon myrtle plantation.
By 1997, the farming operations began in earnest, and today the company that Milgate and Betts head up, Australian Native Foods Management Ltd. (ANFM), operates the largest lemon myrtle plantation in the world, with more than 1.4 million trees situated on a 1500-hectare farm. They anticipate 23,500 tons of dry leaf production over the next 15 years, or an average of more than 1500 tons per year. While other smaller plantations exist, none come close to the size of ANFM's operation, which currently controls 91 percent of the world's lemon myrtle.

Harvesting & Processing
While the cultivation of lemon myrtle has been attempted in China and Malaysia, the failure of these efforts suggests that the plant is destined to stay close to its Australian roots. That's fine by Milgate, who is understandably proprietary about his endeavor. "It took us five years to build the knowledge about how to propagate and grow lemon myrtle," he says. "We have never published the secrets and never will."
Like a kangaroo or koala, lemon myrtle is a uniquely Australian offering that thrives in the sub-tropical forests and rainforests of Queensland. The Conway mountain range where ANFM has established its lemon myrtle plantation experiences "dry tropical conditions"-sub-tropical conditions with average temperatures of 25 to 30 degrees Celsius and average rainfall of 94mm-that are difficult to find elsewhere in the world.
ANFM's multi-million-dollar operation harnesses cutting-edge technology without cutting corners on environmental stewardship. Fully computerized misting sprayers keep 150,000 cuttings alive with collected rainwater stored in large holding tanks. While the particular cultivar of lemon myrtle has thrived well for thousands of years in the rainforest that surrounds ANFM's plantation, growing any plant in large concentrated numbers presents environmental challenges.
Choosing to work with nature rather than against it, ANFM employs sustainable agriculture techniques, such as a balanced fertilization program, mulching and other mechanical controls to ensure its lemon myrtle is completely organic. (While the company's lemon myrtle is fully certified organic in Australia and is recognized for it by the USDA, ANFM is still waiting to receive an official USDA seal for its products.)
For all this high-tech agronomy, however, the place still manages to, as Milgate puts it, "look like a tea plantation." While lemon myrtle can easily grow to 30 meters in the wild, the trees are manicured to a more manageable one-meter height, for much the same reason tea plantations keep Camellia sinensis at bay-convenience. Specially modified mechanical tea harvesters perform a crown harvest, taking only the fresh leaf growth from the trees. While such harvesters can compromise the final quality of Camellia sinensis leaves, the heartier lemon myrtle leaf (it belongs to the eucalyptus family) is not damaged by mechanized harvesting, says ANFM's Betts. Harvesting occurs from April through December, with the January to March break coming only because of monsoon season, when fields are generally too soggy for harvesting.
Once the lemon myrtle leaf is harvested, it is dried in hot air driers that are specially designed to dry the leaf without robbing it of any of its vital citral essential oil. And for the time being, these drying techniques will remain, as Betts puts it, "in-house information." The quality of the bulk leaf remains consistent year-round, although Manik Jayakumar, president of Qtrade International, the leading importer of bulk lemon myrtle to the U.S., notes that citral compound levels do have minor seasonal fluctuations, but generally remain between 90 and 95 percent.

Character Profile
The leaves of the lemon myrtle tree are between 90 and 98 percent citral, an oily compound with a strong lemony profile. Nothing in the plant world comes close to the citrus intensity of lemon myrtle, so its taste often surprises first-time drinkers. Ahmed Rahim, co-owner of Numi Tea, a tea wholesaler based in Oakland, Calif., says that most people marvel at the purity of the flavor, a taste he describes as "more lemon than the taste of lemon, but without the tartness or bitter astringent aftertaste."
"It has an excellent, sweet, lingering flavor," adds Jayakumar. "Very cleansing, but not in an overly medicinal way." The real promise for lemon myrtle, however, lies in its potential as a blending ingredient. The highly aromatic-yet non-acidic-quality of its leaf, combined with its caffeine-free profile, has made it a recent darling of tea manufacturers in the U.S. and abroad. In fact, tea companies, such as Tazo, Peet's Coffee & Tea, and Numi, are quickly incorporating lemon myrtle into their blended tea offerings. And ANFM has recently paired lemon myrtle with black and green teas in a "Native Tastes" brand of lemon myrtle-based teas.
At specialty beverage trade shows this spring, several tea manufacturers will be rolling out lines that prominently feature lemon myrtle. In particular, Jayakumar sees the pairing of green tea and lemon myrtle as a natural winner. "Most people in the States never grew up drinking green tea, so even if they want to like it for its health benefits, the taste profile can be a bit weak for them," he says. "Adding lemon myrtle gives them a familiar citrus flavor while adding another layer to the health story."
For Rahim, lemon myrtle "adds a beautiful balance to any combination of tea-a crisp, clear taste that finishes any cup beautifully." He also admires the tea's consistency. Whereas traditional lemon-based flavorings, such as lemongrass or lemon verbena, tend to fluctuate over time, lemon myrtle's profile is constant. "The fact that lemon myrtle comes from a single location with a unique set of climatic conditions is a big part of this consistency," Rahim says.
Numi's latest offering, "Rainforest Green," takes lemon myrtle from Australia's rainforest and mixes it with yerba maté from South America's rainforest. The result is a light green-colored blend that is earth-friendly, healthful and flavorful. Rahim advises tea blenders who are working with lemon myrtle for the first time to know that it can quickly overwhelm a blend. "Start with a small amount and build slowly," he says.
Beyond its potential in tea blends, lemon myrtle is also emerging as a culinary flavoring agent. Its ability to add a rich citrus flavor to a variety of meats and fish without any lingering bitter or tart notes provides an exciting new cooking option with which chefs the world over are beginning to experiment. Several Australian chefs featured lemon myrtle in their rack of lamb at a recent culinary World Cup in Germany and walked away with gold medals. And according to Milgate, "lemon myrtle has made its way into at least a dozen new recipe books published in Australia over the last five years."
Closer to home, I used some leaves recently in a rotisserie chicken in my own kitchen, and the result was incredible. The acids in most lemon-based flavoring agents tend to introduce a biting quality to the meat that the tongue easily confuses for dryness, but lemon myrtle provides a more complex citrus flavor that seems to work with the meat's natural juices rather than against them. Cast another vote for lemon myrtle as the next "best thing."

Health Benefits
Part of the growing enthusiasm for lemon myrtle is generated by its touted health properties. The plant is registered as a medicinal tree with the Australian government, and numerous Australian therapeutic authorities recognize its medicinal properties. In a 1991 article from The Australian Journal of Medicinal Herbalism, Naturopathic Doctor Andrew Pengelly reported the oil of lemon myrtle "to be anti-fungal, antiviral, a calmative, and a sedative."
Similar health benefits were well documented for the citral compound in its essential oil form long before the commercialization of lemon myrtle. Given the hundreds of scientific publications supporting citral's legitimacy, as well as the high concentration of citral found in lemon myrtle, the potential health benefits of the plant seem hard to ignore.
Increasingly, numerous scientific studies specifically examining lemon myrtle are underway. One study, through Charles Sturt University in New South Wales, found that lemon myrtle "has very good antibacterial activity and excellent antifungal activity."
But while ANFM has commissioned a number of studies to verify lemon myrtle's health benefits, Milgate hopes people will find out about the medicinal qualities slowly. "We want them to enjoy the flavor rather than take it as a medicine," he says. Still, ANFM's lemon myrtle is the best-selling herbal tea in Malaysia, where it is commonly sold as a health product.
Given its intense, aromatic fragrance and its anti-fungal and anti-bacterial attributes, lemon myrtle is also becoming a popular ingredient for a variety of aromatherapy and skin care products, from soaps and shampoos to lip balms and perfumes.

The Outlook
When asked to predict the potential of lemon myrtle in the tea market, Jayakumar says, "Three years ago when I started with bulk lemon myrtle, I imported a pallet's worth. Today, I import a container's worth." ANFM estimates that North America represents only about 15 percent of the company's current lemon myrtle exports, with Asia and Europe accounting for the majority of sales. There is enormous potential for growth in the U.S., not only as a flavoring agent for teas, but with a variety of other products.
In its country of origin, lemon myrtle has already taken off. Its versatile profile has landed it in more than 40 Australian commercial food products, including ice cream, cheese, breads, sauces, syrups, beverages, flavored oils, and more. And as a spice, lemon myrtle is becoming a staple of the Australian restaurant industry, where it is used to add a zesty punch to fish, seafood, poultry, mayonnaise, vinaigrettes, sauces, and desserts.
Lemon myrtle arrives on the scene touting some impressive attributes: an adaptable flavor profile; organic harvesting and processing; exciting health potential; and a boon to rainforest biodiversity. What other flavoring agent in recent memory can claim such a positive litany of attributes? Great thing is, the reality of lemon myrtle might just outlive its own hype.

Allen Kinast is a freelance writer based in Portland, Oregon.