The rumor list was released in October: sugar substitutes can be eaten openly, and only zero addition is a good soy sauce …
[rumor]
◎ Our reporter Chen Xi
In October, "all technology and hard work" became the hottest "stalk". The emergence of this hot spot has aroused people’s attention to food safety, and related rumors have also been widely spread, such as "sugar substitutes can be eaten openly" and "only zero addition is a good soy sauce" … … Rumors about the COVID-19 epidemic still appear from time to time, such as "scanning the code when going out in public places can avoid becoming a secret contact". In addition, the previous drought in some parts of China made the rumor that "precipitation can be artificially increased as long as there are clouds" spread widely.
Today, the reporter of Science and Technology Daily will take stock of the rumors that appeared in October one by one to help you clear the fog and find the truth.
Can sugar substitutes be eaten open?
Truth: Eating a lot of sugar substitutes also poses health risks.
With the approach of winter, people’s time for outdoor sports gradually decreases. Many people began to worry about insufficient calorie consumption, so they paid special attention to controlling calorie intake. Sugar substitute drinks and snacks marked "Zero Sugar" and "Zero Card" seem to contain no calories. Some people think that sugar substitute is healthy, so they don’t have to bear the "sweet burden" and can eat it openly. So, is this really the case?
"This view is wrong. Sugar substitutes should also be eaten reasonably, and there are also health risks when ingested in large quantities." Zheng Yunliang, director of Tianjin Institute of Modern Health Technology, said.
According to the data, sugar substitute refers to alternative sweeteners, which belong to food additives, and there are three main categories — — Natural sweeteners, sugar alcohols and artificial sweeteners. At present, most sugar substitutes on the market use artificial sweeteners, such as aspartame. This kind of sweetener does not exist in nature, but is synthesized by chemistry.
"From the perspective of energy production, sugar substitutes can be divided into nutritional and non-nutritional types. Almost all the decomposition products of non-nutritive sugar substitutes in human body do not contain glucose and do not directly participate in insulin secretion. Therefore, only in theory, non-nutritive sugar substitutes will not cause an increase in blood sugar. " Zheng Yunliang said.
However, this does not mean that we can eat sugar substitutes openly.
"The sweetness of sugar substitutes can stimulate appetite, and excessive intake may cause diarrhea, which may also increase the burden on the kidneys." Zheng Yunliang further said that with the progress of science and the deepening of research, most scientific research results show that artificial sweeteners may have pathogenic risks.
For example, on September 7, 2022, the British Medical Journal published a large-scale research result from France. This study shows that using artificial sweeteners instead of sugar in food or drink is not beneficial to the cardiovascular and cerebrovascular health of the whole population. Cell magazine also published a related study, which found that the intake of artificial sweeteners was related to the changes of intestinal microbiota and the increase of blood sugar.
Therefore, Zheng Yunliang suggested that consumers should try to choose foods containing natural sweeteners when choosing sugar substitutes, such as erythritol, stevioside, momordica grosvenori glycoside, sweet tea glycoside and so on.
"It is safe to eat food or drinks instead of sugar occasionally, so you don’t have to be overly nervous. The public should scientifically understand and eat sugar substitutes and improve their health through scientific and reasonable diet and exercise. " Zheng Yunliang said.
Can you avoid becoming a secret connector by scanning the code when you go out in public places?
Truth: Repeated code scanning will be considered as entering the place many times.
As a normal prevention and control measure of epidemic situation in COVID-19, scanning code before entering public places has been integrated into people’s daily life. However, a "special reminder" appeared in the WeChat circle of friends a few days ago: after scanning the code into a public place, scan the code again when leaving, and big data will "think" that you have gone out; If an infected person enters the site again, big data can "prove" that you and the infected person do not overlap in contact time, and you can avoid becoming close contacts.
In this regard, relevant departments in Shanghai, Shandong, Sichuan, Zhejiang, Fujian, Inner Mongolia, Liaoning and other places have all rumored. Experts from Dongying Big Data Center said that "place code" is a special two-dimensional code given to a place, which is used to identify the location, name and other information of the place and plays an important role in epidemic prevention and control in COVID-19. When someone scans the "place code", it can only show that they have been to the place. Using big data means can’t distinguish whether the person is in the "entry" or "departure" state.
In addition, relevant experts said that scanning the code twice may be considered as entering the place twice, which will not achieve the effect mentioned in the rumor, but will increase the workload of the flow control personnel and indirectly affect the epidemic prevention and control work. Experts reminded that the public only need to scan the code when entering the place, and there is no need to scan the code after going out. If the relevant staff find that the risk of infection of the code scanner is high, they will inform the code scanner in time and take prompt measures to avoid the spread of the virus.
Only zero addition is good soy sauce?
Truth: The quality of soy sauce depends on many factors.
Not long ago, the "additive" storm of a brand of soy sauce caused many consumers to talk about the color change of additives, so many people took the absence of additives as the standard for evaluating the quality of soy sauce.
"This statement is not entirely correct." Zheng Yunliang said that the so-called zero-added soy sauce is soy sauce with special color, fragrance and taste made by microbial fermentation without adding any monosodium glutamate or food additives. However, the quality of soy sauce depends on many factors, and zero addition is only one of them.
"First of all, the soy sauce listed should meet the relevant national standards." Zheng Yunliang introduced that China’s "National Standard for Food Safety Soy Sauce" (GB 2717-2018) stipulates that soy sauce is a liquid condiment with special color, fragrance and taste made from soybeans and/or defatted soybeans, wheat and/or wheat flour and/or wheat bran as the main raw materials through microbial fermentation. Soy sauce manufacturers shall have a complete fermentation and brewing process, and shall not use raw materials such as acid hydrolyzed vegetable protein seasoning liquid to produce soy sauce.
Soy sauce that meets the relevant national standards has reached the "passing line", but it is not high quality.
"Soluble solids, chloride, total nitrogen, total acid and reducing sugar in soy sauce are important quality evaluation indicators, which can affect the quality of soy sauce." Zheng Yunliang introduced that the umami taste of soy sauce depends on the content of amino acid nitrogen. Generally speaking, the higher the content of amino acid nitrogen, the higher the grade and the better the quality of soy sauce.
At the same time, as a traditional fermented condiment in China, the flavor of soy sauce is also an important quality index. The differences in koji varieties and technological processes of different soy sauces will make them have great differences in flavor.
According to related technical literature, 230 nonvolatile compounds were detected in soy sauce, including 90 peptides, 49 organic acids, 27 amino acids and their derivatives, 28 sugars, 11 sugar alcohols, 6 biogenic amines, 4 nucleotides and 16 other compounds, which determined the acidity, sweetness and concentration of soy sauce.
In addition, Zheng Yunliang reminded that consumers should also have a rational understanding of additives and not be overly superstitious about zero-added food.
"In soy sauce processing, the most commonly used food additives are sodium benzoate, disodium inosinate and disodium guanylate. Rational use of food additives can prevent bacterial growth, moderately extend the shelf life, and make soy sauce more cost-effective. " Zheng Yunliang said.
In fact, instead of paying attention to food additives, consumers should pay more attention to the sodium content in soy sauce.
"In every 100ml of soy sauce, the sodium content is about 6g, and the recommended intake of sodium is only 2g/day. Related studies have shown that excessive intake of sodium may lead to cardiovascular diseases such as hypertension and arteriosclerosis. " Zheng Yunliang reminded.
As long as there are clouds, it can artificially increase rainfall?
Truth: Certain conditions are needed, and the key is to have the right cloud.
Since this summer, the drought in the eastern part of southwest China, the south of the Yangtze River and the northern part of South China has continued to develop, and it has suffered from drought in summer and autumn. The water levels of Poyang Lake and Dongting Lake all hit record lows, and some lakes even became "deserts" and "grasslands". At the same time, there is a question on the internet: as long as there are clouds, artificial precipitation can be carried out. Why not carry out artificial precipitation enhancement in these arid areas?
In this regard, Wang Zhaoyu, director of the Tianjin Office of Weather Modification, said that artificial precipitation enhancement is not artificial rainfall, and "turning clouds into rain" requires certain conditions.
Artificial precipitation enhancement is to influence the microphysical process of clouds through artificial intervention under appropriate weather conditions, so as to increase the ground precipitation.
"The way of artificial intervention is mainly by sowing catalysts into the cloud. Generally speaking, the catalysts sown in the northern region are mostly silver iodide, while dry ice and liquid nitrogen are commonly used as artificial precipitation enhancement catalysts in the southern region. In addition to catalysts, there are ways of manual intervention, such as emitting femtosecond laser and charged particles to the cloud. " Wang Zhaoyu said that no matter which way is used, the ultimate goal is to form condensation nuclei, promote water vapor condensation, and finally form precipitation.
However, a clever woman can’t cook without rice. In this process, the most crucial thing is — — There should be a cloud that meets the conditions of artificial precipitation enhancement. Such a cloud needs to have a certain thickness, height and temperature, and at the same time, the water vapor in the cloud should be abundant and just in the updraft area.
Wang Zhaoyu explained that the medium and low clouds with a temperature of MINUS 10 to 0 degrees Celsius, a thickness of about 2,000 meters and a height of less than 6,000 meters are suitable for artificial precipitation enhancement. Such warm clouds are full of small water droplets, which float in the air and cannot fall down under the support of updraft, forming clouds; With the help of the catalyst, increasing the concentration of condensation nuclei in the cloud can make small water droplets collide more and more into large water droplets, and then form precipitation.
















