25% of grain and oil is contaminated by fungal toxins, and mold prevention and control cannot be ignored
Everyone knows that moldy food cannot be eaten. Moldy peanuts, moldy corn, moldy rice - once accidentally eaten, the effects range from vomiting in mild cases to death in severe cases. This is because these moldy foods contain a hidden killer of food safety——fungal toxins.
Since the ergot poisoning incident in 11th-century Europe, humanity saw the dangers of fungal toxins for the first time. From then on, scientists officially began a prolonged battle against fungal toxins. However, humanity has not completely defeated them. In 2012, with strong support from relevant government departments, the Institute of Food Science and Technology of the Chinese Academy of Agricultural Sciences, together with Jiangnan University, Shandong Agricultural University, the Nanjing Research Institute for Agricultural Mechanization of the Ministry of Agriculture, the Jiangxi Academy of Agricultural Sciences, the Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences and other institutions, launched a special scientific research project for public welfare industries (agriculture)——"Research on Control Technology for Fungal Toxins in Grain and Oil," once again declaring war on fungal toxins.
Today, with the successful pilot demonstration of the integrated control technology for fungal toxins in grain and oil developed by experts in the project team, humanity finally has the opportunity to say “no” to mold in grain and oil and to take the initiative in this “blocking battle.”
Current situation
⟦NL> Mold produces fungal toxins; about 25% of grain and oil worldwide is contaminated by them
What are fungal toxins? How are they produced? Liu Yang, a researcher at the Institute of Food Science and Technology of the Chinese Academy of Agricultural Sciences and chief scientist of the project, who has long been engaged in fungal toxin research, explained to reporters: “Fungal toxins are produced by mold. They are secondary metabolites produced by fungi and mainly include aflatoxins, zearalenone, deoxynivalenol and so on. From corn, wheat and peanuts to fruits, seasonings, Chinese medicinal materials, feed and milk, fungal toxins are almost everywhere in our production and daily life.”
As toxins with strong toxicity and carcinogenicity, fungal toxins can contaminate almost all types of edible and feed agricultural products. According to statistics from the Food and Agriculture Organization of the United Nations, about 25% of grain and oil worldwide is contaminated by fungal toxins each year. In recent years, the problem of fungal toxin contamination in agricultural products has been a hot food safety issue of great concern to countries around the world.
In our country, the contamination situation with fungal toxins is likewise not encouraging. According to reports, due to the influence of individual farmer planting and storage methods, as well as the high-temperature and high-humidity weather in the Yangtze River Basin and South China, products such as corn, wheat, rice, peanuts, dried fruits and Chinese medicinal materials in our country are severely contaminated by fungal toxins, with annual cumulative losses of grain and oil of about 31 million tons. It can be said that the problem of fungal toxin contamination in grain and oil products has become an important hidden danger to our country's food security and food safety, seriously endangering people's health.
Because of the serious harmfulness of fungal toxins, countries around the world have not only formulated corresponding limit standards and regulations, but their limit standard values have also continued to decrease, becoming increasingly strict. And in the 10 years from 2001 to 2011, among cases of food violations in our country's exports to the EU, those exceeding fungal toxin limits accounted for 28.6%, a very high proportion for a single type of incident.
“Fungal toxin contamination of grain and oil occurs at every stage of planting, harvesting, storage and processing. It has become an important bottleneck restricting our country's agricultural production, economic development and international trade, and it seriously affects our food security and food safety. How to scientifically and effectively prevent and control fungal toxin contamination is already extremely urgent.” Liu Yang said.
Integration
Prevention and control at every stage of planting, storage and processing is indispensable
“We have already developed some prevention and control technologies for each production stage of grain and oil, but the key next step is how to systematically integrate and assemble these technologies, promote them and put them into practice.” Liu Yang explained that, unlike previous fungal toxin prevention and control research, the project focuses on grain and oil crops such as wheat, corn, rice and peanuts, and systematically carries out research on control technologies for the entire industrial chain of fungal toxins in grain and oil around stages such as field production, harvesting, storage and processing. “In preventing and controlling fungal toxins, no stage can be left out.”
It is currently the peanut harvest season in the south. At the experimental demonstration base of the Suiyuan Peanut Planting Professional Cooperative in Yicheng Town, Zhangshu City, Jiangxi Province, reporters saw that, compared with the diseased peanuts harvested in farmers' fields, the peanuts in the experimental field were all plump and clean. Shang Bo, an experimental staff member at the Institute of Food Science and Technology of the Chinese Academy of Agricultural Sciences, explained: “For the peanuts in this field, during the pegging stage of peanut flowering we applied our own developed biocontrol microbial agent against aflatoxin. After treatment, through several years of continuous experimental testing, basically no aflatoxin has been detected in the harvested peanuts.” Shang Bo said that this biocontrol microbial agent can be used not only on peanuts, but also on corn.
In addition to field prevention and control during the planting stage, scientists have also developed many low-cost and easy-to-apply clever methods for the storage stage of grain and oil. Drying and storing peanuts has always been a headache for farmers, but in the warehouse of the Suiyuan Cooperative, reporters saw two drying devices designed and developed by the Nanjing Research Institute for Agricultural Mechanization of the Ministry of Agriculture working busily. “This kind of drying equipment can effectively help farmers solve the problem of peanuts, rice, corn and wheat being difficult to dry in rainy weather. It is easy to learn, and the equipment can not only be disassembled and transported, but also costs about 40,000 yuan, which farmers can fully accept.” introduced Dr. Fu Xiaoji of the Jiangxi Academy of Agricultural Sciences. For storage packaging, the cooperative uses a new type of light-blocking vacuum-packaging plastic bag. As long as peanuts are sealed and stored in the plastic bag, even if kept for a year, they will not become damp or moldy.
Prevention and control of fungal toxins during processing is likewise a difficult point. “We have specially developed technologies, products and equipment such as sorting and removal of contaminated raw materials, removal during processing and biological adsorption to degrade and remove fungal toxins.” Xing Fuguo, associate researcher at the Institute of Food Science and Technology of the Chinese Academy of Agricultural Sciences, told reporters that each technology in the processing stage is accompanied by the development of new equipment or new products, truly bringing high-end technology down to earth.
If a product contains fungal toxins, how should it be detected and detoxified? Do not worry - scientists also have methods. In the project team's laboratory at the Yicheng Town base, researchers demonstrated to reporters a detoxification experiment on grain and oil food that exceeded standards. The researchers dropped a fungal toxin detoxification enzyme preparation into a sample contaminated with fungal toxins. One hour later, using a rapid detector, the final test data showed that even if the fungal toxins in the sample exceeded the standard by 5 times, after 1 hour the toxin content had dropped below the national limit standard.
Promotion
Integrated technology is easy to learn and use; the cost of microbial agents and equipment is not high
50-year-old Deng Genqing is the person in charge of Jiangxi Xiangcheng Natural Food Co., Ltd. and also the chairman of the Suiyuan Peanut Professional Cooperative. Since 2012, he has begun cooperating with the project team and became the first direct beneficiary of the integrated prevention and control technology.
“There is a lot of rain in the south, and the annual peanut harvest season is when I have the biggest headache. And how to prevent and control aflatoxin during processing is also a difficult problem, which directly affects the quality of our peanut oil products.” Deng Genqing told reporters that for peanut processing enterprises, aflatoxin has always been a formidable enemy. If you defeat it at one stage, it emerges at another, making it quite difficult to prevent and control. Now, Deng Genqing's fields use biocontrol microbial agents, his warehouse uses drying equipment and vacuum plastic bags, and his processing workshop uses a series of specialized equipment such as moldy peanut sorting machines, detoxification machines and detectors. “Now, with the complete set of supporting technologies, my peanut quality is fully guaranteed, and the products sell better too.”
“Judging from the results of these 4 years of experimental demonstration, these technologies and devices are very easy to use, and the actual cost of promotion is not high either.” Xing Fuguo told reporters that, taking only the biocontrol microbial agent used in the planting stage as an example, the cost is only 6 yuan per mu, and this microbial agent is effective for many years after one year of treatment. “In addition, this microbial agent is developed from local fungi as raw materials. They are all ‘native’ to their original habitat, so there is no hidden danger of invasive alien species.” Xing Fuguo added half-jokingly.
Similarly, the selling price of peanut drying and ventilation equipment is only about 40,000 yuan, while the vacuum plastic bags used in the storage stage cost 3 yuan each and can be used for storage for more than a year with no problem, and the plastic bags can also be reused for many years. “For farmers, these technologies of ours are all easy to learn and easy to operate. As long as each stage is implemented according to standards, fungal toxins can definitely be effectively prevented and controlled.” Deng Genqing said with emotion.
“Fungal toxins are everywhere. Their prevention and control concern the food safety and food security of our more than one billion people. In this campaign to ‘block’ fungal toxins, there is still much we must strive to do and many difficult problems we must overcome.” Speaking of future scientific research work, Liu Yang hopes to accelerate the promotion, application and popularization of these efficient and mature technologies, and to contribute to ensuring our country's food safety, food security and exports of grain and oil products.