Dongeejiao is a traditional Chinese tonic that is one of the three treasures, along with ginseng and pilos antler, in the bible of traditional Chinese medicine. [Photo by Yang Feiyue/China Daily]

Securing enough donkeys is just one of many steps the brand has taken to revive its past glory.

Qin Yufeng, president of Dongeejiao, says: "We have retained our traditions to ensure quality, but also try to boost efficiency where possible.

"For example, we use digital technology to control water content in the gelatin," he says.

Also, every donkey has an identity electric chip embedded in its neck.

The chip ensures that the donkey hide is traceable.

But certain processes are still traditional, says Qin, adding: "For instance, we still use coarse homespun cloth, dip it in highly purified water, and then hand-wipe the condensed gelatin to increase its luster."

In the drying process, workers also need to press down the gelatin when it curls due to lack of water content.

Then, the gelatin pieces are wrapped in brown paper and put in wooden box for storage.

"These things cannot be done by machines," he says.

Qin, who has rosy cheeks and good skin, says: "I owe my health to donkey hide gelatin,"

Qin, who joined Dongeejiao as a temporary worker at 16, says he learned the process from Liu Xuxiang, whose family had been in the business for several generations.

Everything was traditional when Qin began his career, he says.

Then, the hide had to be soaked in water and the fur had to be removed by hand before being dried.

Later, the hide had to be cut into squares before being put away for stewing.

The stewing of the hide was hard, he says, adding: "Steam filled the room, and you couldn't even see your hands. "My clothes would be drenched in sweat in winter, and I would smell bad."

Roughly 30 workers would take turns to watch a big pot, and control of the fire was the key in determining the quality. Then, when the hide turned into gelatin, it needed to be condensed.

The whole process could last from five months to a year. The difficult work conditions did not put Qin off as he believed the skills could help him going far.

The years of hard work eventually paid off when Qin rose to the top of the company.