When macadamia nuts turn into 'Liquid Gold' good for health

Wednesday, July 1, 2026, 07:10 (GMT+7)

With no chemistry degree and no massive capital, Mr. Duong Xuan Qua personally extracts macadamia essential oil valued at 50 USD per milligram from a small workshop in the Central Highlands.

The journey to create "liquid gold"

Mr. Duong Xuan Qua (born in 1957, from Long Xuyen, An Giang) is widely known by the moniker "king of dryers". This is not a self-proclaimed title, as through decades of traveling from the Mekong Delta to the Central Highlands, and as far as Lang Son, Lao Cai, and Lai Chau to sell paddy drying machines, he is one of the rare individuals who understood why traders refused to buy the dried paddy, and he personally modified the machines that farmers had struggled with for a decade.

It was this profession of selling paddy dryers that led him to the macadamia warehouses in the Central Highlands around 2017 - 2018. And he noticed what no one else paid attention to. "Traveling extensively, I became familiar with almost everything. Only this was unusual, so I looked into it," he recounted.

The "unusual" thing Mr. Qua saw were bags of macadamia nuts lying dead in the warehouse—damp, yellowed, leaking oil, and emitting a foul odor. Upon inquiring, he discovered that imported drying machines required up to 85 hours to dry the macadamia nuts, while domestic machines took 100 or even 120 hours; they were slow, energy-consuming, and yielded inconsistent quality. Farmers looking for technical documentation to improve the drying technology found none, and machine manufacturers considered their responsibility fulfilled once the equipment was sold

In 2021, right during the Covid-19 pandemic, Mr. Qua stayed home and began researching macadamia nut dryers. He designed a three-function washing machine: separating defective floating nuts, cleaning the husks, and eliminating micro-fungi attached to the fresh husks to prevent mold during storage. Next was a grading roller to sort three nut sizes, because if the nuts are not uniform, the drying temperature cannot be evenly distributed. Following that was a touch-screen controlled dehumidification cabinet for which he established the technical requirements and hired an electronics team to custom-design it to his specifications.

But the most critical aspect did not lie in the machinery. It lay in a simple discovery Mr. Qua learned from an engineer: to determine the moisture content of macadamia nuts, dry 1kg and weigh it repeatedly. When the weight no longer decreases, that is when the moisture content has reached 0%.

Based on that principle, he developed a 45-hour drying process, cutting the time by nearly half compared to foreign machines, and the processed macadamia nuts can be safely stored for up to a year. His machines became bestsellers from Lam Dong to Lang Son. The revenue from selling machines served as the capital that sustained him through his subsequent years of macadamia research.

Everywhere Mr. Qua went, people were extracting macadamia oil from yellowed, damaged, and rejected kernels. The premium kernels were sold, and only the unsellable ones were fed into the oil press. The extracted oil had a different color everywhere, varying odors in each batch, and completely lacked standardization.

“People say macadamia oil is precious, but if you use poor-quality raw materials, the oil holds no value and can even be toxic,” Mr. Qua stated. He purchased macadamia oil from various places for comparison. By observing the color and smelling the aroma, he decided to start from scratch using grade 1 kernels that were dried strictly according to his own protocol.

During the first batch dried for oil extraction, the dryer's control software malfunctioned; he had to stay awake all night alongside an electronics technician, troubleshooting continuously to prevent the batch from spoiling. Ultimately, the dried nuts came out dry and crisp, and the pressed oil was clear. He consulted a chemistry Ph.D. acquaintance at Can Tho University. The brief answer was: it is highly beneficial for skin and hair.

Back in 2020, he dyed his hair, which subsequently fell out gradually over two years. Every time he bathed, his hands would be covered in loose hair. Hearing that macadamia oil was good for hair, he dipped a brush into the oil and applied it to his scalp every other day.

“I just applied it, not actually expecting my hair to grow back. But surprisingly, 20 days later, I looked at my hands after bathing and there wasn't a single strand of hair,” he recounted. He asked his wife to part his hair roots to check. His wife confirmed that his hair was growing back, one or two centimeters long, and very dense.

From that moment, he knew he was approaching something extraordinary. He spent over 13 million VND to send macadamia oil samples to a center in Ho Chi Minh City for testing and compositional analysis. The returned results were filled with chemical terminology, so he sought a Ph.D. working at the Vietnam Academy of Science and Technology to interpret the data. The Ph.D. reviewed the analysis and messaged him: your oil contains a rare compound; if isolated, it is valued at 50 USD/milligram.

That compound is 1-palmitoleyl-2-oleyl-3-stearoyl-glycerol. He did not know the detailed applications of this compound, only that it possesses strong antibacterial properties and promotes skin regeneration.

The macadamia essential oil also contains Omega-7, a compound he understands very well. Omega-7 facilitates rapid wound healing, including open wounds in diabetic patients. His wife suffered from varicose veins, and after using macadamia oil for a period, they almost completely returned to normal.

Furthermore, he spent 20 million VND to commission the translation of 12 international scientific papers on macadamia oil to understand what global scientists were saying about it.

Deep processing leads to wealth

From every 1kg of macadamia kernels, Mr. Qua extracts 700 grams of oil, 200 grams of fine powder, and 100 grams of macadamia butter. These figures may sound ordinary at first glance, but when combined, the value-add is substantial.

He purchases 1.3kg of fresh in-shell raw macadamia nuts for about 120,000 VND. After drying, the 1.3kg yields 1kg of dried nuts (approximately 110 large-sized nuts), from which he produces 55 bottles of oil (5-milligram type), wholesaled at 50,000 VND/bottle, thereby generating a total of 2,750,000 VND in oil revenue from just 120,000 VND of raw materials.

Standard edible macadamia oil only sells for 800,000 VND/liter, whereas the specialized oil containing 24 compounds is priced at 4.2 million VND/liter. For the exact same liter of oil, the price difference is more than 5 times greater simply due to the differing drying process.

The press cake remaining after oil extraction is often fed to livestock or discarded in many facilities because the oil cannot be fully separated. Mr. Qua devised a method to exhaustively extract the oil from the press cake, then milled it into a fine powder capable of dissolving completely in water. He discovered that macadamia nuts lack hard insoluble fiber and contain only soluble fiber. This powder is beneficial for the stomach, aids in relieving acid reflux, and sells for 1 million VND/kg.

The hard nutshells—which export containers discard by the tons—he processes into activated carbon used for exfoliating dead skin cells.

His current business model remains small, with an average monthly revenue of around one hundred million VND. For the first 3 - 4 years, he gave away the deep-processed macadamia products for free, refusing payment, until actual consumers returned to seek them out, at which point he began selling. A spa owner spotted a bottle of oil displayed on a table at an automation exhibition, tested it on her hand, walked around, and returned to note that the oil absorbed extremely fast, leaving a dry finish without greasiness. A week later, the spa owner contacted him to purchase 2 liters. That was his first order.

He currently holds a license for edible oil extracted from macadamia nuts, but he is still waiting on the skin and hair care oil because doing it properly requires passing cosmetic testing standards. He remarked: “I am a farmer, no one simply believes what I say. If you want people to believe, you must let them touch reality.”

His greatest aspiration is not merely to sell a large volume of oil: "I want to prove that macadamia nuts, when processed correctly, will become a precious medicinal herb of the Central Highlands. Currently, people only know it as the queen of dry nuts, meant purely for snacking.”

Minh Toan

Source: Khi hạt mắc ca hóa thành ‘vàng lỏng' 

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