Today, for Arabica coffee growers in Vietnam’s Central Highlands, the coffee hulling machine has become commonplace—many families have bought one for their own production. Yet few know who the “father” of this machine is, where it originated, or when the first machine appeared.
From Blacksmith to Inventor
Currently, Arabica coffee hulling machines are widely sold on the market, as many people can now make them to supply local coffee farmers—so they no longer need to hull beans by hand as in the past. But the very first version of the Arabica coffee hulling machine in Vietnam came from Xuân Trường Commune (Đà Lạt City), one of the most important Arabica coffee-growing areas of Lâm Đồng Province. It was invented by Mr. Trương Diên Tỵ (58 years old) in the years just after the country’s liberation. Speaking of Mr. Tỵ, Mr. Hà Phước Ta, Party Secretary of Xuân Trường Commune, expressed great admiration: “He has created many remarkable things that everyone must respect!”
Mr. Trương Diên Tỵ recalls that as a child he traveled with his father across the province, earning a living by forging sickles, hoes, shovels and other tools. By the age of 15, he had mastered all his father’s blacksmithing skills. From then on, he specialized in forging sickles for the French to cut tea at plantations in Xuân Trường, Bảo Lộc, and Di Linh. After national liberation, the French tea plantations were handed over to the Vietnamese. Much of the tea-growing land was converted to Arabica coffee. His own family’s tea land was quickly planted with coffee to improve their livelihood. But at harvest time, coffee growers had to work day and night, expending tremendous effort yet still unable to hull the coffee promptly. Farmers picked coffee during the day and then pounded it at night by the light of kerosene lamps to separate beans from their skins—leaving them exhausted and with little time for rest.
Becoming an Inventor
Watching his elderly mother—frail and weak—still using her strength to pound coffee cherries to extract the beans, Mr. Trương Diên Tỵ began tinkering. He modified the family’s cassava grinder, which he and his father had built earlier, into a hand-cranked coffee huller using a wooden shaft. At first it was just an experiment, but the economic benefits quickly became clear: it required far less labor than pounding by hand and separated the coffee skins much faster. Seeing how convenient the machine was, many families in Xuân Trường came to order one. From then on, Mr. Tỵ switched entirely to manufacturing coffee hulling machines for local farmers.
After making several dozen machines, one day while picking coffee he noticed a brook gurgling at the foot of the hill. An idea struck him: harness the power of running water to replace human effort in turning the machine’s shaft. Back home, he forged a set of turbine blades and attached them to the wooden shaft so that the water flow would automatically rotate the shaft, allowing the machine to hull coffee right at the plantation without waiting to return home.
When Xuân Trường later had access to the electrical grid, Mr. Tỵ quickly improved his machine again. He upgraded all the parts to steel to withstand the vibration when powered by an electric motor. The machine consisted of a top hopper to hold the coffee cherries. When the motor ran, it rotated the steel shaft, causing the coffee cherries to fall and rub against each other, breaking their skins before being discharged onto a screen. The beans would drop below while the husks exited through another outlet. According to Mr. Trương Diên Tỵ, his invention can separate up to 90% of the coffee beans cleanly. Though the machine looks simple, every part must be built and assembled precisely. Otherwise, the machine may crush the beans or fail to hull properly.
Seeing how practical Mr. Tỵ’s invention was, many coffee-growing families in Đức Trọng, Lâm Hà, and Di Linh flocked to order machines. To date, he estimates that he has produced over 2,000 coffee hullers for farmers inside and outside the province, each priced between 7 and 10 million VND. He has also trained many local mechanics to make these machines to meet the growing demand from coffee growers across the Central Highlands.
Mr. Hà Phước Ta, Party Secretary of Xuân Trường Commune—who witnessed the invention from start to finish—said that today many people can produce coffee hulling machines, but the ones built by Mr. Tỵ remain superior: they hull cleanly, with husks and beans separated into two distinct channels. “It’s a pity that Mr. Trương Diên Tỵ never registered for intellectual property rights, so his interests are not legally protected,” Mr. Hà Phước Ta remarked. As for the inventor himself, Mr. Trương Diên Tỵ simply smiled wryly and said, “I only made it to help farmers reduce hardship in production, not with any ambition of becoming an inventor.”