If the grain feed is not completely dry at harvest, or the temperature or humidity is too high during storage and transportation, the fungi infected with the grain feed will grow rapidly. Almost all fungi (storage fungi) growing in grain depots will infect seed embryos, which will lead to the decline of grain germination rate and produce toxins. The moisture content of grain is an important factor for the growth and toxin production of fungi. Generally, when the relative humidity of grain is lower than 70% and the moisture content of grain is lower than 15%, the growth of mold can be controlled.
Most fungi can grow at 20-28℃, the growth of fungi is obviously weakened below 10℃ or above 30℃, and it can hardly grow at 0℃. Generally speaking, controlling the temperature can reduce the production of mycotoxins. However, some Fusarium can produce toxins on winter grain at 7℃. The lowest growth temperature of Aspergillus flavus is 6-8℃, and the highest growth temperature is 44-46℃. The yield of aflatoxin B 1 was the highest at 32℃. Interestingly, microbiologists have found a microorganism that can produce aflatoxin inhibitor, and the application of this inhibitor has greatly reduced the pollution of aflatoxin.
People's Daily Online, Beijing, May 20 (Reporter Mary) Chen Mengshan, Party Secretary of China Academy of Agricultural Sciences, pointed out at the 20 14 international mycotoxin conference today that according to the statistics of FAO, 25% of agricultural products in the world are contaminated by mycotoxins every year. In China, agricultural products are seriously polluted by mycotoxins due to farmers' personal planting and storage methods, the influence of high temperature and high humidity weather in the Yangtze River basin and South China, and the influence of consumption habits.
According to the statistics of the Institute of Agricultural Products Processing of Chinese Academy of Agricultural Sciences, during the ten years from 200 1 to 20 1, there were 2,559 illegal incidents of food exported from China to the European Union, of which mycotoxin exceeded the standard, accounting for 28.6%, which was higher than the public's well-known factors such as heavy metals, food additives and pesticide residues, and the proportion was the highest in a single incident. Liu Yang, a researcher at the Processing Institute of the Academy of Agricultural Sciences, who is the chairman of the meeting, believes that excessive mycotoxins have become the biggest obstacle for China's agricultural products to export to the EU, causing huge economic losses to China's grain and oil processing and export enterprises.
What is mycotoxin? Why can it cause such amazing damage? Data show that mycotoxins are secondary metabolites produced by fungi, mainly including aflatoxin and Fusarium toxin. As early as 1 1 century, there were descriptions of mycotoxin poisoning in European icon paintings, but it was not until 1960 that more than 654.38+million turkeys in Britain died from feeding aflatoxin-contaminated feed that mycotoxin was re-recognized. Affected by global warming, drought and other factors, edible and feed agricultural products are increasingly polluted by mycotoxins, and there are more and more reports about mycotoxin pollution around the world. Sometimes, multiple mycotoxins can be detected in the same area, or the same mycotoxin can be reported all over the world at the same time. Pollution is not limited to corn, wheat, barley, peanuts and other grains, but also includes dried fruits, fruits, Chinese herbal medicines, milk and so on.
"The government of China attaches great importance to the prevention and control of mycotoxins," said Jin of the Agricultural Products Quality and Safety Supervision Bureau of the Ministry of Agriculture. The Ministry of Agriculture and the Ministry of Science and Technology started relevant research and pollution investigation successively, and published and revised the limit standards of mycotoxins in 2005 and 201year respectively, which reduced the harm of mycotoxins to human health to some extent. "In recent years, there have been no poisoning incidents caused by mycotoxin pollution in the world."
Liu Yang believes that the holding of the international mycotoxin conference in China, known as the "Olympics" in the field of mycotoxins, will not only build a platform for the exchange and discussion of the latest detection, monitoring, early warning, prevention and control technologies and strategies of mycotoxins at home and abroad, but also show China's efforts and achievements in the field of mycotoxin prevention and control, which will help to improve China's international influence in this field and its right to speak in the formulation of international limit standards or regulations.