By Yin Hang

The Hunan provincial agriculture authority denied Monday that the sale of soybeans dyed green had spread to other cities in the province after local media reported that the problematic product was found in Hengyang.

The report said some peddlers dyed dry soybeans to make them look like fresh green beans for greater profits, which drew health concern.

"We have not yet found the colored soybeans at other places until now," an official with the Hunan provincial agriculture law enforcement team, surnamed Huang, told the Global Times Monday.

Huang added that the authority would oversee the issue.

Hengyang agricultural authorities detected some street peddlers soaking dry soybeans in green pigment and sodium pyrosulfite and then selling them as fresh green beans.

The authority found about 500 kilograms of dry soybeans and green beans, 5 kilograms of sodium metabisulfite, and food dye in a workshop near a local vegetable market, Hunan Economic TV reported.

A kilogram of dry soybeans can produce 1.8 kilograms of dyed green soybeans and a bag of 50 kilograms of dry soybeans can fetch an extra profit of 200 yuan ($29) to 300 yuan ($44) after the green dye treatment, the report said.

Sodium pyrosulfite is a chemical additive that is often used as a bleaching agent in preserved fruit, bamboo shoots, and mushroom products, according to the current hygienic standards of food additives.

"Although legitimate intake of this additive will not pose any harm to the body, excessive intake of any additive will put a burden on the liver and kidneys," Fan Zhihong, a food safety professor with the China Agricultural University, told the Global Times.

The Global Times' calls to the Hengyang agricultural authority went unanswered Monday.

A restaurant manager in Hengyang surnamed Yang told the Global Times that local restaurants seldom use green beans in dishes now.

"They take more time to cook compared with other vegetables. In addition, green bean dishes are cheap compared to meat dishes," Yang said.

"We can hardly earn any profits by offering them," he added.

Xie Wenhui, a food stall owner in the same city, told the Global Times yesterday that few people would eat green soybeans, because it is not the right time of the year to eat them.

Xie said green soybeans usually mature in the summer.

"I did not find colored soybeans in the market nearby. Even if they really exist, no one would order and eat them. It would be weird to eat them right now," Xie said.

The report said the dyed beans could also be found at supermarkets in the neighboring city of Changsha, also the capital of the province.

However, agriculture inspector Huang told the Global Times that the authority has not received any reports of colored soybean cases in the city.

"We will keep a close eye on that and inform the public when we have any further information," he said.