The storm of "Pu 'er tea causes cancer" has resurfaced.
In July, the popular science magazine Science World published an article entitled "Can drinking tea prevent cancer or cause cancer? Taking Pu 'er tea as an example, "Pu 'er tea on the market generally contains aflatoxin and other mycotoxins, and some of them are still very high." Therefore, drinking Pu 'er tea will do harm to the human body. "Acute injuries are easy to find, while chronic injuries, such as cancer, are invisible."
This paper also provides a lot of evidence to support the viewpoint, such as "In 20 10, researchers from Guangzhou Center for Disease Control and Prevention randomly selected 70 samples of Pu 'er tea in Guangzhou market, and found that aflatoxin could be detected in all of them, and the content of aflatoxin in 8 samples exceeded the aflatoxin limit (5 μ g/kg) stipulated by China Grain Standard. At the same time, it was also found that all Pu 'er tea samples contained fumonisins and emetic toxins, and the content of emetic toxins in 63 samples exceeded the limit set by the standard (1 mg/kg) ". In addition, "in 20 12, a graduate student of food engineering in Nanchang University repeated the research of Guangzhou CDC, and the results were consistent with those of Guangzhou CDC. 60 Pu 'er teas were collected from Nanchang market, all of which could detect aflatoxin, and 7 of them exceeded the standard. All fumonisins and vomiting toxins were also detected, and 4 1 serving of vomiting toxins exceeded the standard. "
In addition, the article also cited a case from the Department of Nephrology, Maanshan Central Hospital, Anhui Province in 20 12 to prove that aflatoxin and other mycotoxins contained in Pu 'er tea can do harm to human body. According to the article, "A patient drinks10g of Pu 'er tea every day, and after drinking for more than one month, aflatoxin poisoning leads to acute liver damage".
Expert: "This is irresponsible and out of context."
After this article was published, many "tea fans" fell into "fear" for a while. However, it has also been strongly opposed by many experts in the tea field.
"Pu 'er tea can cause cancer because aflatoxin is detected? Isn't this a problem that has been refuted by experiments in 20 12 years? " At the symposium on the same day, Zhou Hongjie, a professor at Yunnan Agricultural University, said that as early as 20 12, the research team of the school showed through simulated fermentation experiments that during the fermentation of Pu 'er tea, although Aspergillus flavus could grow and reproduce in tea samples at the initial stage, the growth of Aspergillus flavus was obviously inhibited in the later stage, and aflatoxin was not produced when the fermentation was terminated.
Gao Zhao, a professor at Yunnan University, also said that the growth condition of aflatoxin is that the basic substance of aflatoxin action must be substances containing protein, sugar and fat. Although Pu 'er tea also contains a very small amount of protein, starch and fat, the content is very small, and it will be transformed during fermentation. Due to the lack of material conditions for transforming aflatoxin, it is almost impossible for Pu 'er tea to produce aflatoxin. It's just that some inferior tea leaves are polluted by the environment because of improper storage.
Shao Wanfang, a professor at Yunnan Agricultural University, pointed out, "Can drinking tea prevent cancer or cause cancer? The spot check of Guangzhou Center for Disease Control and Prevention and the research of graduate students of Nanchang University cited in the article are to understand the contamination of mycotoxins in Pu 'er tea stored in wet storage, and the samples are all wet storage Pu 'er tea, not normal Pu 'er tea. "It is irresponsible to quote out of context."
"Without the representativeness of the sample, there will be no correctness of the results." Shao Wanfang revealed that Yunnan Agricultural University will organize experts from a number of domestic scientific research units to sample old tea 1 10,000 copies in warehouses in key areas where Pu 'er tea is stored nationwide to test whether there is aflatoxin in tea. Two months later, speak with scientific data.
Industry: "Frequent storms will protect rights by legal means"
"In fact, it is not the first time that Pu 'er tea is carcinogenic. Similar voices come out every few years. " Xu Kun, vice president of Yunnan Pu 'er Tea Association, clearly remembers that the pig farm fermentation incident in 2007 and the 20 12 "Pu 'er Tea Carcinogenesis Theory" both pushed Pu 'er tea to the forefront.
"I don't deny that it is inevitable that some businesses in an industry will have unqualified products for their own interests. But now, the Pu 'er tea industry has strict national standards. Products produced by regular enterprises must be sent to the National Pu 'er Tea Quality Supervision and Inspection Center for testing, and there will be no molds such as Aspergillus flavus harmful to human body. " Xu Wei said.
Zhang Shungao, a leading figure in Yunnan tea industry, said frankly, "Whenever there is a voice questioning Pu 'er tea, the Pu 'er tea industry is also seriously thinking about it. In recent years, the Pu 'er tea industry has introduced many standards in order to give consumers better products. "
In the view of Lu Guoling, a senior Pu 'er tea expert and former deputy director of Menghai Tea Factory, "the storm of Pu 'er tea is wave after wave. It is better to do your own thing than to fight a war of words. "
Wang Xingyuan, director of Yunnan Tea Industry Office, believes that this storm may become an opportunity to upgrade Pu 'er tea. "Yunnan tea industry will continue to strengthen its technology with the support of science and technology. At the same time, for those who are maliciously seriously injured in Pu 'er tea, legal measures will also be taken to protect their rights. "