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"When it's freezing cold
Give me a thermos cup
I can soak up the whole world."
Thermos cup, just have a good appearance can not be
For the health care family, the best partner of the thermos cup is no longer the "unique branch" of goji berries, but also can make tea, dates, ginseng, coffee... However, recent surveys have found that some thermos cups on the market have shoddy quality problems. What the? Problems with quality? The insulation effect is a little worse? NO！ NO！ NO！ The heat preservation is almost barely endured, but the problem of heavy metals exceeding the standard is big!
Face value is the basic "responsibility" of a thermos cup, but when you hold it in the palm of your hand, you will find that more important than the face value is the material.
The thermos cups are mostly made of stainless steel, which is resistant to high temperatures and has good thermal insulation performance. Other materials such as glass, ceramics, purple sand, etc., are affected by factors such as insulation, anti-fall and price, and are only a handful of the insulation cup army.
Stainless steel materials are generally divided into three types, "code names" are 201, 304 and 316.
201 stainless steel, good at camouflage "Li Ghost"
Most of the unqualified thermos cups exposed in the news use 201 stainless steel as the liner of the thermos cups. 201 stainless steel has a high manganese content and poor corrosion resistance, if it is used as the inner tank of the thermos cup, the long-term storage of acidic substances may lead to manganese precipitation. Manganese metal is an essential trace element, but excessive intake of manganese can hurt the body, especially the nervous system. Imagine if you let your child drink this water all day, the consequences are really serious!
304 stainless steel, real material is very "carrying"
Stainless steel is in contact with food, and its safety hazard is mainly the migration of heavy metals. Therefore, stainless steel in contact with food must be food grade. Food grade stainless steel is most commonly used in 304 stainless steel with good corrosion resistance. To be named 304, it needs to contain 18% chromium and 8% nickel to be justified. However, merchants will mark the word 304 in the obvious position of stainless steel products, but labeling 304 does not mean that it meets the requirements for food contact use.
316 stainless steel, aristocratic origin is not stained with "mortal dust"
304 stainless steel is more acid-resistant, but when encountering substances containing chloride ions, such as salt solutions, it is still prone to spot corrosion. The 316 stainless steel is the advanced version: it adds metal molybdenum on the basis of 304 stainless steel, so as to have better corrosion resistance and more "carrying". Unfortunately, 316 stainless steel has a high cost and is mostly used in high-tech fields such as medical treatment and chemical industry.
There are hidden dangers, soaking should not be soaked
The thermos cup is the thermos cup, and the bubble goji berries will also be obtained, and the natural bubble cannot be soaked all over the world! Not only that, some things that are commonplace in daily life cannot be soaked in the thermos cup.
1
Tea
Brewing tea with a stainless steel thermos cup will not cause metal chromium migration, nor will it cause corrosion to the stainless steel material itself. But even so, it is not recommended to use a thermos cup to make tea, this is because tea is usually suitable for brewing, long-term hot water soaking, will destroy the vitamins in the tea, but also reduce the flavor and taste of tea. Moreover, if the cleaning is not timely and thorough after brewing, the tea scale will be attached to the inner tank of the thermos cup, resulting in an odor.
2
Carbonated drinks and juices
Carbonated drinks, fruit juices, and some traditional Chinese medicines are mostly acidic, and they are placed in the thermos cup for a short time and will not cause heavy metal migration. However, these liquids are complex in composition, some are more acidic, and long-term contact may corrode stainless steel, and heavy metals will migrate to drinks. When using the thermos cups to hold carbonated drinks and other gas-producing liquids, pay attention not to put too much, too full, but also avoid violent shaking, so as not to dissolve the gas escape, the pressure in the cup will also occur when the safety hazards will also occur.
3
Milk and soy milk
Milk and soy milk are both high-protein drinks that are easy to spoil in the case of prolonged heat preservation. Milk and soy milk that have been placed in the thermos cup for a long time, if you drink it in one go, it is difficult to think of diarrhea! In addition, the proteins in milk and soy milk are also easy to adhere to the cup wall, making cleaning difficult. If you only temporarily use the thermos to hold milk and soy milk, you should also disinfect the thermos cup with hot water first, drink it as soon as possible, and clean it as soon as possible. When cleaning, try to be "gentle" and avoid the use of hard brushes or steel wire balls to prevent scratching the surface of stainless steel and affecting corrosion resistance.
Tip: Pick your thermos cup this way
First, buy through formal channels and try to select products of well-known brands. Consumers should pay attention to checking whether the instruction manual, label and product certificate are complete when purchasing, and avoid buying "three no products".
Second, check whether the product identifies its material type and material composition, such as austenitic SUS304 stainless steel, SUS316 stainless steel or "stainless steel 06Cr19Ni10" and other words.
Third, open the thermos cup and smell it. If it is a qualified product, because the materials used are food grade, there is generally no odor.
Fourth, touch the mouth of the cup and the inner tank with your hand, the inner tank of the qualified thermos cup is relatively smooth, while the inferior thermos cup is mostly rough due to material problems.
Fifth, accessories such as sealing rings and straws that are easy to contact with liquids should use food-grade silicone.
Sixth, after purchase, water leakage and thermal insulation performance tests should be carried out first, and the holding time usually needs to reach more than 6 hours.
The author | Lin Xiao, Environmental Chemistry Department, Institute of Environmental and Health-related Product Safety, Chinese Center for Disease Control and Prevention
Audit | expert of the National Health Science Popularization Expert Database
Cheng Yibin, researcher at the Institute of Environmental and Health-related Product Safety of the Chinese Center for Disease Control and Prevention
Planner | Tan Jia Yu Yunxi
Editor| Wang Jianying