Pack fruit, cooked food, leftovers … Are you using the plastic wrap correctly?

Products such as plastic wrap and fresh-keeping bag can be seen everywhere. We are used to tearing off a piece of plastic wrap to seal the cut watermelon and other fruits, and opening a fresh-keeping bag to repackage dishes to prevent cross-taste.

What gives these materials the ability to "keep fresh"? What should I pay special attention to when using it?

Types of plastic wrap

Pe (polyethylene) cling film

The main component of pe cling film is polyethylene resin, which is mainly used for packaging ordinary fruits and vegetables.

Pe plastic wrap is considered as a safe packaging material, which can package foods that come into direct contact.

Pe plastic wrap has good waterproof and air permeability, and is suitable for packaging fresh vegetables and frozen foods. However, due to its good air permeability, it is not suitable for packaging foods with high oil content and easy to be spoiled by oxygen.

Pvc (polyvinyl chloride) preservative film

Pvc is a kind of polymer compound formed by addition polymerization of vinyl chloride monomer, which has the characteristics of good transparency, high viscosity and good elasticity, but these characteristics are based on its great harm to people.

The monomer vinyl chloride of pvc has anesthetic effect, teratogenicity and carcinogenicity at the same time. Long-term contact will cause harm to human nervous system, liver and embryo, and its human safety limit is 1 mg/kg body weight.

At the same time, the thermal stability of pvc preservative film is poor, and heating or microwave treatment will cause it to crack and produce toxic vinyl chloride.

In addition, in order to make pvc material into a soft and transparent preservative film, it is inevitable to add plasticizer to change its property state during manufacturing.

Some pvc cling films may contain ethylhexylamine (deha) as a plasticizer, which will destroy the endocrine system of human body, be carcinogenic, and be easily separated from the packaging materials and enter the human body with food.

Therefore, the General Administration of Quality Supervision, Inspection and Quarantine requires food preservative film manufacturers to indicate the material and scope of application on the product packaging, and it is forbidden to use deha in the production of pvc preservative film, and it is also forbidden to directly package meat, cooked food and oily food with pvc preservative film.

Pvdc (polyvinylidene chloride) cling film

Pvdc cling film is composed of polyvinylidene chloride, a small amount of plasticizer, stabilizer and other additives, which is mainly used for packaging some cooked food, ham and other products. It has the characteristics of good freshness, firmness and easy attachment, and can prevent water evaporation. It is superior to pvc preservative film in heat resistance and safety.

Pvdc cling film can be used for both refrigerator preservation and microwave heating, and its temperature range can reach -60℃~140℃.

Plastic wrap is not everything.

Plastic wrap has the advantages of preventing food from cross-flavor, reducing bacterial pollution and maintaining food nutrients.

It has certain air permeability and limits the loss of water, can adjust the oxygen content and water content around food, and at the same time block dust and bacterial pollution to a certain extent, thus prolonging the shelf life of food.

But it is not a "universal product" for food preservation.

Plasticizer will dissolve into food in water or oil above 60℃, so it is best not to keep cooked food and food containing a lot of oil with plastic wrap.

Fruits and vegetables with high moisture content are more suitable for preservation with plastic wrap, such as apples, pears and watermelons.

It is recommended to choose pe plastic wrap, especially when it is used for meat, fruit and other foods.

Pvdc plastic wrap has better moisture retention, and can provide longer fresh-keeping time compared with pe plastic wrap.

When buying plastic wrap, you should pay attention to the specific name or chemical formula on the package, and at the same time, you must choose products marked with the words "food use".

ShangguanNo. Author: Shanghai Huangpu

Today’s beginning of spring | Do these 3 points in health care and live up to the good times in spring.

This article is transferred from [China CDC trends];
Click on "China CDC News" above to subscribe!
Today ushered in the first of the 24 solar terms-beginning of spring.
"Stand, built also. Spring begins and is established. "Keeping in good health in beginning of spring is a wonderful beginning for a whole year.
The sunrise wind and hangover wake up, and the mountain family is happy for the rest of their lives.
The snow is abundant in the past three years, and the suburbs are warm and green in spring.
-(Song) Excerpts from Lu You’s beginning of spring Day
Spring cattle spring staff, infinite spring breeze to the sea.
Then with the spring workers, dyed pink like meat red.
-(Song) Excerpts from Su Shi’s "Minced Magnolia beginning of spring"
There are three periods in beginning of spring: "when the east wind thaws, when the stinging insects start to vibrate, and when the fish get cold".
The east wind warmed up and the earth began to thaw. After five days in beginning of spring, the dormant insects slowly woke up in the cave. After five days, the ice in the river began to melt and the fish began to swim on the water.
☆ Health should protect the liver ☆.
The three months of spring are the season of bringing forth the old and bringing forth the new and sprouting life.
The attribute of five elements in spring is "wood". "Mu Yue Qu Zhi", that is, upward growth and outward stretching, has the characteristics of growth and rising hair, and the functional characteristics of "liver" in five internal organs are similar to those of gasification in spring.The liver has the function of regulating emotions and dispersing qi, so spring corresponds to the "liver" in the five internal organs.
In order to relieve liver qi, people should get up early, dress loosely and exercise properly in this season to make their spirits relaxed and keep their vitality in the body.Don’t be overworked or angry, otherwise it will easily damage the liver. Please put away three ways to nourish the liver.
one Sleep nourishing liver
After beginning of spring, the days became longer and the nights became shorter. In order to adapt to this day and night change,You can go to bed late and get up early appropriately, but you should also pay attention to "getting up early is not before the crow, and getting up late is not after sunrise". Generally, you should go to bed no later than 23: 00, and it is best to go to bed at 22: 00.Ensure sleep during this period, which is beneficial to the maintenance of liver and gallbladder.
2 Exercise nourishing liver
Huangdi Neijing says that in spring, "lying at night and getting up early, striding in the court" requires that people should take proper exercise in the morning in spring, thus contributing to the regulation of liver-qi and the growth of yang.Baduanjin, a fitness skill, is a very suitable choice for middle-aged and elderly people. Practicing Baduanjin regularly is an effective way to keep the liver healthy.
three Eat sweet and nourishing the liver
In spring, the yang rises, and the metabolism of the human body is also vigorous. Neijing holds that "acrimony and sweetness diffuse into yang", so it is advisable to eat more acrimony and sweetness in spring diet to help the liver-qi disperse and avoid sour products.
Sweet and sweet herbs can be dispersed into yang to nourish the liver,Warm food is good for protecting yang, such as onion, coriander, leek, jujube and peanut.Blue food often enters the liver meridian, which has the effect of clearing liver fire.Those who are prone to hot spring can eat more green vegetables, such as celery, spinach, cucumber and bell pepper.
☆ Prevention of Four Diseases in beginning of spring ☆
It’s early spring in beginning of spring, so it’s chilly in spring, so it’s not advisable to cut clothes too quickly. Moreover, because people’s liver qi rises, it is easy to cause recurrence of old diseases at this time, especially the following four diseases, and everyone must pay attention to prevention.
1 Hypertension
Traditional Chinese medicine believes that the onset of hypertension is too related to the rise of "liver qi" and "liver yang". Spring is the season of liver and wood. Anyone with hyperactivity of liver yang is particularly prone to headache and dizziness in spring.
Therefore, once patients with hypertension feel dizzy and head pain, they should not only monitor their blood pressure, but also adjust their antihypertensive drugs in time under the guidance of doctors, and pay attention to a light diet.Control the intake of salt, cholesterol and fat, strictly quit smoking and limit alcohol, and prevent and treat hypertension and its complications. This kind of patients, in the diet, should mainly prevent liver yang from rising too much, and eat more foods such as acidic convergence.
2 peptic ulcer
Huangdi Neijing holds that liver qi is easy to attack the stomach and suppress the spleen, so spring is also a season of recurrent gastric and duodenal ulcers, which may cause symptoms such as bloating in the upper abdomen, pain, frequent belching, acid regurgitation and loss of appetite, and even bleeding and perforation.Therefore, the spleen and stomach should be fully nursed back to health in spring.
3 mental illness
There is a folk saying in our country that "cauliflower is yellow and idiot is busy".Spring is the season of high incidence of mental diseases, so we should pay attention to the prevention and treatment of mental diseases in spring, pay more attention to psychological care and care, and never interrupt drugs without authorization.
fourChronic liver disease
Spring is the best time to nourish and protect the liver, and it is also the season with frequent liver diseases. At the same time, spring is also the best time to treat liver diseases. Liver wood is flourishing in spring, and the qi of liver wood is flourishing. At this time, effective treatment can achieve twice the result with half the effort.Drink less, be less angry and move more, so that the whole body and mind can return to a natural state, which is conducive to nourishing the liver.
Beginning of spring today.
A new year has begun.
May you enjoy a wonderful holiday.
Live up to spring.
Find infinite vitality!
(Source: Healthy China)
Reporting/feedback

Brush the screen! The 63-year-old chairman of China’s largest gold mine married his 38-year-old wife. The company has a market value of 150 billion yuan. Bride: Believe in love!

Source: China Gold Online Network
A shares closed in September: the Shanghai Composite Index fell by more than 5% in five consecutive Yin San stock indexes.
Is it love or money behind the marriage with a difference of 26 years?
On October 7th, the wedding of Chen Jinghe, chairman of Zijin Mining, was brushed on Weibo Hot Search.
Image source: Sina Weibo
The bride said at the wedding that true love can cross and break through the boundaries of age. The groom is the owner of the largest gold mine in China, and the market value of listed companies exceeds 150 billion. The bride, Ms. Qian Bing, is an economist and M&A dealer.
The video circulating on the Internet shows that at the wedding, the bride Qian Bing teased that when she first met Chen Jinghe, the mining expert might have found that the girl in front of her was a high-grade gold mine.
The wedding is hotly debated.
It is said that in China, gold has Chen Jinghe, copper has Wang Wenyin and aluminum has Zhang Shiping.
According to the data, 63-year-old Chen Jinghe graduated from Fuzhou University with a master’s degree in geology, a professor-level senior engineer, enjoying special allowance from the State Council, a deputy to the Tenth People’s Congress of Fujian Province, and a vice president of the China Gold Association. From 1986 to 1992, he worked in Minxi Geological Brigade, was the main discoverer and exploration organizer of Zijinshan Copper Mine, and served as the chairman of Zijin Mining since 2000.
While netizens are curious about what kind of beautiful woman the chairman of this listed company with a market value of over 150 billion yuan married, the 25-year-old age difference between 63-year-old Chen Jinghe and 38-year-old newlywed wife also triggered a heated discussion among netizens. Some netizens said that they "don’t believe in love", and some netizens thought that "a perfect match is a blessing".
Net biography, the bride’s name is "Qian Bing", an American MBA, who has served as the vice president of the channel department of a famous financial company for many years, and is an economist and M&A trader. In this regard, some netizens ridiculed that this marriage is the most successful merger and acquisition made by Ms. Qian.
Image source: Netease News
Many netizens have begun to express "believe in love"
It is understood that Chen Jinghe was not married for the first time. His first wife Lai Jinlian died of illness in January 2013, and Chen Jinghe sent a special message to mourn his beloved wife.
Wind data shows that Zijin Mining has a total market value of 156.1 billion yuan and a total share capital of 25.4 billion shares. The latest share price of A shares is 6.15 yuan, and the share price of Hong Kong stocks is 5.16 Hong Kong dollars. The actual controller of Zijin Mining is Minxi Xinghang State-owned Assets Investment Management Co., Ltd.
According to the 2019 annual report, as of the end of last year, Chen Jinghe held 127 million shares, which was not among the top ten shareholders.
Image source: the company’s 2019 annual report
According to the semi-annual report of Zijin Mining in 2020, on July 27th, 2020, Chen Jinghe transferred 51 million A shares of the company to his son due to the arrangement of family property distribution. According to the latest stock price calculation, these shares are worth 314 million yuan.
Image source: 2020 semi-annual report
As of the reporting period, Chen Jinghe still holds 76.05 million shares of the company (including 15 million H shares). According to the latest stock price calculation, its market value of A shares is 375 million yuan, and the market value of Hong Kong shares is 77.4 million Hong Kong dollars.
Flying out of overseas "black swan"
In April this year, Zijin Mining announced that the company’s Bogla gold mine project in Papua New Guinea (hereinafter referred to as "Papua New Guinea") did not obtain the application for extension of the special mining rights of the Papua New Guinea government.
The data shows that from 2017 to 2019, the mineral gold of Zijin Mining was 37.48 tons, 36.5 tons and 40.83 tons respectively. In 2019, the company got 8.83 tons of equity output from Bogla Gold Mine, which was the largest source of mineral gold, accounting for about 21% of the company’s total mineral gold in that year. The company’s second and third largest gold mines did not exceed 6 tons. Zijin Mining said that the suspension of production of Pogra gold mine will have a greater impact on the company’s gold production. Affected by this, Zijin Mining’s share price plummeted by more than 9% the day after the announcement, and fell by nearly 10 billion yuan in just one day.
According to the latest news of mining journal, on September 25th, the Supreme Court of Papua New Guinea rejected the application for the renewal of the mining right of Bogla Gold Mine. The Supreme Court of Papua New Guinea also ruled that the gold mine will be operated by the Papua New Guinea state-owned enterprise Kumur Mining Holdings Co., Ltd.
Meanwhile, on September 30th, PNG Prime Minister James Marape issued a statement: "I urge barrick companies to be humble and abide by the rule of law." According to the statement, in the mining development contract signed by barrick and PNG Mineral Resources Administration in 1989, there was a clause that reserved the government’s right to Pogra Gold Mine, namely, "Pogra Gold Mine became a national asset on the date when the mining right expired, and the state did not bear any expenses or compensation."
Although the "black swan incident" was exposed, the shares of Zijin Mining A shares and Hong Kong stocks have been on the rise since March. Among them, in just 113 trading days from March 19 to September 1, the cumulative increase of A-share price was as high as 119.28%, and then it fell back.
Source: Wind
As for the decline in output that may be caused by the extension of the application for renewal of mineral rights in Bogla Gold Mine, Chuancai Securities believes that Zijin Mining’s acquisition of Buritika Gold Mine and Guiana Gold Field will increase the production capacity of 13 tons of mineral gold, which can effectively make up for the decline in output that may be caused by the extension of mineral rights in Bogla Gold Mine. In the future, the company’s mineral gold output will grow steadily and remain above 40 tons.
Reporting/feedback