4hw.com.cn: fresh keeping film has become an essential product in our life. We wrap most of the unfinished fruits, vegetables and rice with plastic wrap. In this way, it feels like it can really keep fresh. In fact, not all foods are suitable for the use of preservative film. Fruits and vegetables with large water content are more suitable for the use of preservative film. Cooked food, hot food, and food containing oil, especially meat, should not be packaged with preservative film for storage. Can the plastic wrap be heated?
How to choose fresh film? Can the plastic wrap be heated?
Types of preservative film
At present, most of the fresh-keeping films sold on the market are made of ethylene masterbatch, just like the plastic bags in common use. According to the different types of ethylene masterbatch, the fresh-keeping films are divided into three categories.
It is polyethylene.
PE (polyphylene) for short, this material is mainly used for food packaging, such as the fresh-keeping film for fruits and vegetables we usually buy, including semi-finished products purchased in supermarkets.
It's PVC
PVC (polyvinylchloride) for short, this material can also be used in food packaging, but it has a certain impact on the safety of human body.
It's polyvinylidene chloride
PVDC (polyvinylidene chloride) is mainly used to pack some cooked food, ham, etc.
Experts said that among the three kinds of fresh-keeping films, PE and PVDC are safe for human body and can be safely used. PVC film is harmful to human body.
The plasticizer used for PVC film is mainly composed of ethylhexylamine (DEHA). This kind of substance is easy to separate out. With the food brought to human body, it has carcinogenic effect, especially the disorder of endocrine and hormone, causing breast cancer of women, congenital defect of newborn, decrease of sperm number of men, and even mental illness
How to choose fresh keeping film
'look':
See if it has any product instructions. If it's covered with PE film or polyethylene film, you can use it at ease.
Touch:
Polyethylene fresh-keeping film generally has poor viscosity and transparency, which is easy to open after rubbing by hand, while PVC fresh-keeping film has better transparency and viscosity, which is not easy to open after rubbing by hand, and easy to stick on the hand.
'burn':
After the polyethylene film is ignited by fire, the flame is yellow, and it will not go out when it leaves the fire source. There is oil dripping and no pungent smell.
The quality and technical supervision department hopes that consumers should not forget to take a look at the material before purchasing the plastic wrap. If there is PE plastic wrap or polyethylene plastic wrap written on it, they can use it at ease. If there is PVC or unspecified material written on it, they should try not to buy it
Can the plastic wrap be heated
Not all foods are suitable for the use of preservative film, cut watermelon, meat, etc. it is better not to use; PE, PVC film should not be heated. Not all foods are suitable for the use of preservative film, fruits and vegetables with large water content are more suitable for the use of preservative film, while cooked food, hot food, and food containing oil, especially meat, it is better not to use preservative film packaging for storage. High fat foods will absorb more plasticizers, more at room temperature than at cold storage. PVC fresh-keeping film shall not contact with greasy food and shall not be used at high temperature. Select the food grade PE resin that meets the requirements, do not need to add plasticizer, and the film blowing manufacturer can produce PE fresh-keeping film according to the normal process, so there is no need to worry about DEHA, DEHP, etc. PVDC film is similar. Therefore, the safety of the film is mainly focused on PVC film. Some plasticizers must be added in the PVC processing to increase the toughness of the film, which will move out with time and certain environmental factors. The key of harm lies in the quantity of moving out and transferring into food. Generally speaking, food heating and contact with grease will lead to higher migration of plasticizer.