Interpretation of the eight hottest rumors in the food industry in 2014

Editor's words: there is no shortage of rumors in life, especially in today's information age, the generation and spread of rumors are far more violent than refuting rumors. With the help of mobile new media, the food circle has become the most likely area to attract attention and rumors. As 2014 is almost over, this edition invites authoritative food experts to select the hottest rumors in the food industry of the year and interpret them one by one.

1. Anti-aging of small molecular collagen.

Rumor tracking: at the beginning of the year, artist Lin Zhiying became a hot topic with "reverse growth". Among the products launched by his company, there is a collagen drink with "small molecular collagen" as the main raw material, which Lin Zhiying says is the secret of not being old.

Expert interpretation: Yun, PhD in Food Engineering, Department of Agriculture and Biology, Purdue University in the United States, said that there is no evidence that hydrolyzed collagen (or "small molecular collagen") can help beauty and skin care. Hydrolyzing collagen is equivalent to carrying out part of the process of human digestion in vitro, which is faster to digest and absorb after eating. In addition, many dipeptides and tripeptides in hydrolyzed collagen are directly absorbed into the blood, but they can not enter the cells as raw materials for protein synthesis. In other words, they are indeed absorbed into the bloodstream, but they cannot be used, and are eventually excreted out of the body.

2. Oxygen-rich water can "replenish oxygen"

Rumor tracking: you can "replenish oxygen" by drinking water, and the content of dissolved oxygen is 6 to 10 times that of ordinary drinking water. At the end of February, Hangzhou Wa Group launched an oxygen-rich weakly alkaline water known as a "revolutionary drink", claiming that drinking a bottle of oxygen-rich water could absorb high concentrations of oxygen in the water through mucosal infiltration of the digestive tract.

Expert interpretation: Yun said unintentionally, first of all, oxygen-rich water is not magical, opening the bottle will release oxygen. Secondly, it is not realistic to absorb oxygen by drinking water. Water is drunk into the digestive system, although "scientists" put forward the theory of "absorbing high concentrations of oxygen in water through mucosal infiltration of the digestive tract", but it has not been recognized by the scientific community. Replenishing oxygen by drinking water is not true in theory. Finally, compared with breathing, the oxygen content in the water is too low. Even if all the oxygen in oxygen-rich water can be absorbed by the human body, the amount is very small compared to breathing.

3. Genetically modified food is harmful

Rumor tracking: in early March, many websites launched a documentary on the investigation of genetically modified genes filmed by TV host Cui Yongyuan in the United States, which was widely viewed and forwarded. At the CPPCC meeting, he put forward a proposal to ban the commercialization of genetically modified staple grains and immediately end the GM projects of seed companies.

Luo Yunbo, dean of the School of Food Science and Nutrition Engineering of China Agricultural University, pointed out that so far, no approved GM foods have been found to have any adverse effects on human health. Transgenic plants only change the genes of crops. These altered genes are eaten into the human body and digested together with other genes. They do not change human genes. Genetically modified foods should be strictly evaluated before entering the market. It should be said that the genetically modified foods we can buy are safe and safe to eat.

4. Fruit and milk can not be eaten together

Rumor tracking: various taboos about drinking milk are widely spread among the people. In a TV program this year, experts told everyone not to eat sour fruit within an hour before and after drinking milk through the experiment of "pouring orange juice into milk to produce flocculent precipitation".

Expert interpretation: in this regard, China Agricultural University functional Dairy key Laboratory Dr. Hu Changli said that acid precipitation is the basic property of "casein" in milk. Even if you don't drink it with fruit juice, the milk will precipitate in your stomach. Because there is a large amount of stomach acid in the stomach, its ingredient is mainly hydrochloric acid, which is much sour than the fruit acid in fruit. After the milk enters the gastrointestinal tract, it will first come into contact with gastric acid and flocculate, and then further digest and absorb. On the other hand, fruit and milk are still good partners, and their nutrition is a perfect match.

5. Cancer caused by microwave heating

Rumor tracking: the theory that microwave ovens cause cancer has a long history. This summer, a piece called "stop using the microwave oven, it will cause cancer!" The post went viral on Wechat, saying that food heated in microwave ovens will produce carcinogens, sparking concern again.

Expert interpretation: fan Zhihong, an associate professor at the School of Food Science and Nutrition Engineering at China Agricultural University, pointed out that microwaves only heat water molecules in food, and the food itself does not undergo chemical changes and will not produce carcinogens. Lu Jianguo, director of the Comprehensive Inspection Department of the National Household Appliances quality Supervision and Inspection Center, also said that qualified microwave ovens have undergone strict testing and repeated experiments, and their microwave leakage and radiation are within the range of national standards. Normal use, will not cause harm to the human body, let alone through its heated food.

6. Mushrooms are rich in heavy metals

Rumor tracking: in October, an article entitled "eat less mushrooms" circulated on WeChat, saying that a doctor from the University of Zurich in Switzerland, who studies fungi, said that mushrooms are good. However, it has a strong ability to enrich lead, mercury and other heavy metals, up to more than 100 times.

Expert interpretation: professor Lin Xinying of the Institute of Nutrition and Food Hygiene of Shandong University told reporters that compared with some foods, mushrooms have a high ability to accumulate heavy metals. However, whether the heavy metals exceed the standard or not is mainly related to the growing environment of mushrooms. At present, most of the mushrooms sold on the market are grown in the culture medium containing cottonseed hull, wheat bran and other agricultural and forestry by-products, so they have little chance of exposure to heavy metals, let alone excessive heavy metals. In addition, mushrooms contain polysaccharides, which can inhibit the dissociation of heavy metals, so that they can not become ions in the body, so it is difficult to be absorbed by the intestines. So even if people eat mushrooms, the impact on the human body is relatively small.

7. "Polar Grass" has magical effects

Rumor tracking: polar grass 5X Cordyceps sinensis, a product that claims to be "edible", has the effects of improving human immunity and anti-tumor, is well known for its high price and frequent advertisements. In November this year, Wang Hai, a well-known anti-counterfeiter, submitted the classic lozenges of 5X Cordyceps sinensis for inspection, and the results showed that the lozenges did not contain cordycepin.

Expert interpretation: Yun unintentionally said that Cordyceps sinensis has long been "decrypted" by science-it is just a fruiting body in which fungi attach to insects, kill them and then grow on its corpses. There is no evidence to support the magical effect of Cordyceps sinensis in western studies, but the conclusions tend to be "negative". In the scientific literature, most of the research on Cordyceps sinensis is done by Chinese people, and the research level is basically at the level of "component recognition". It can be said that the research distance of Cordyceps sinensis has been shown to be effective in human trials, and there is still a long way to go. At present, there is no scientific test results show that Cordyceps sinensis buccal tablets are more conducive to absorption or better.

8. Making tea in stainless steel cups is poisonous

Rumor tracking: after winter, some media filmed a video saying that the cup was "corroded" after 72 hours of brewing tea in a stainless steel cup. Because stainless steel contains toxic heavy metal chromium, it will be released into tea.

Expert interpretation: Yun unintentionally said that it is not easy to corrode stainless steel. The corrosion results of stainless steel can be seen by naked eye only if the stainless steel is soaked in strong corrosion condition for a long time. On the other hand, the tea is close to neutral, the ionic strength is also very low, and it is almost non-corrosive, let alone cause visible corrosion within dozens of hours. The most likely is that tea dirt is deposited on the cup and is regarded as "corrosion". In addition, stainless steel will only be corroded in some cases, and some chromium will be dissolved, but the content is very small, so there is no need to worry about the daily use of stainless steel utensils in line with national standards.