High-tech chambers extend tuber shelf life in Hainan

To meet rising global demand, Changjiang Li autonomous county in Hainan province is turning to science to give its sweet potatoes an edge.

The county is using high-tech healing chambers where damaged tubers regenerate before export. The post-harvest treatment extends shelf life and reduces waste, which are key advantages for international shipping.

"Sweet potato skins are delicate and easily damaged during harvest," said Sun Tong, deputy general manager of Changjiang Guangling Agricultural Technology. "If left untreated, these wounds can lead to soft rot or black spot disease in storage."

To solve the problem, the company adopted high-tech healing rooms, where injured sweet potatoes undergo a week-long "heat therapy" at controlled humidity and carbon dioxide levels. The innovation comes as the county seeks to transform its sandy coastal fields into an export powerhouse.

"Damaged sweet potatoes can develop a natural protective layer when treated in a 40 C healing chamber for seven days, effectively blocking pathogens," said Sun. The technique boosts the tubers' healthy yield to 94.7 percent, extends shelf life from one month to over six months, and reduces spoilage rates from 15 percent to 10 percent, enabling year-round supply stability.

"Since December last year, we've exported seven shipping containers totaling 152 metric tons of sweet potatoes to Canada, with positive customer feedback," the company said. An eighth shipment, weighing roughly 20 metric tons, was sent Tuesday.

The company aims to export over 100 shipping containers this year, targeting markets in West Asia, East Asia, and Western Europe. The push aligns with the Hainan Free Trade Port's goal to grow its agricultural exports.

Changjiang grows sweet potatoes on about 16.67 square kilometers, with an annual output value of 230 million yuan ($32 million). The crop accounts for 20 percent of the sweet potato market in the island province, according to data from local authorities.

"We're also building a full supply chain for tropical crops like mangoes and longan," said Sun. "This upgrade helps small farmers meet global standards and transforms local produce into a competitive international commodity."