In China, the largest production areas of Chinese wolfberry are in Ge’ermu City, Qinghai, and Jingyuan County, Gansu. Recently, it was revealed that some merchants in these areas were illegally processing wolfberries to enhance their appearance. On September 1st, this issue came to light. Reports from mainland China indicate that sodium metabisulfite is being added to wolfberries in Ge’ermu City, while the wolfberries in Jingyuan County have excessive sulfur dioxide.
In recent years, wolfberries, as a traditional tonic food, have seen a resurgence in popularity among young consumers. There are over 30,000 companies engaged in wolfberry production and operation in China. The wolfberries found to have safety hazards, originating from the two largest wolfberry production areas in China, Gansu and Qinghai.
According to a report by “Financial Investigation,” manufacturers and merchants in Ge’ermu City, Haixi Mongol and Tibetan Autonomous Prefecture in Qinghai Province, use sodium metabisulfite to enhance the color of wolfberries during production.
Sodium metabisulfite is an inorganic compound with a strong irritating odor. Despite knowing the harmful effects of sodium metabisulfite on the human body, merchants continue to add this chemical agent in order to fetch higher prices.
Merchants have mentioned that for the first and second harvests of wolfberries, a small amount of sodium metabisulfite is sufficient, as an excessive amount makes them appear fake. However, for the third harvest when wolfberries ripen in cooler weather, a large amount of sodium metabisulfite is needed to ensure the berries look vibrant.
Furthermore, there are approximately 280,000 acres of wolfberry cultivation in Jingyuan County, Gansu Province, spread across 14 townships.
Merchants in Jingyuan County explain that after fresh wolfberries are harvested, they must be washed with “sodium hydroxide” solution to ensure the dried berries look bright and attractive. However, in case of rain, the appearance of the wolfberries, even if washed with sodium metabisulfite, is hard to maintain. In such situations, they resort to using sulfur fumigation.
Apart from rain, the low temperatures in Gansu in August can also affect the appearance of wolfberries when sunlight is insufficient. The solution remains to be sulfur fumigation. Some merchants opt to use industrial sulfur to save costs.
Industrial sulfur is not suitable for food processing, as it is toxic and contains high levels of arsenic. Consumption of sulfur-contaminated wolfberries can lead to kidney dysfunction and failure, peripheral neuropathy, and liver damage.
Merchants have admitted that these sulfur-treated wolfberries have found their way into hotpot restaurants, small herbal shops, tea bags, and even wolfberry wine.
The Quality Inspection Station of Ningxia International Wolfberry Trading Center conducted tests on samples from 11 wolfberries from Jingyuan County. Results showed that all samples did not meet the sulfur dioxide standards.
“It’s not just wolfberries,” some internet users commented: “Many products from our hometown used to be treated with sulfur before being sold, or else they wouldn’t fetch good prices, such as dried vegetables and Chinese herbs…” Others mentioned: “To make them look appealing, many fruits undergo various treatments.”