First of all, digital secrets on plastic packaging.
We are all familiar with plastic containers, and careful friends may find that there are some numbers on the bottom or side of plastic containers to identify the types of plastics. Among them, 1 (PET), No.5 (PP) and No.6 (PS) are commonly used materials for take-away packaging boxes.
(Types and applications of plastic products)
Second, often eat food in plastic containers will cause harm to the body?
Some people think that eating food packed in plastic containers often will be harmful to your health, because these plastic containers will release harmful substances, such as plasticizers, bisphenol A, dioxins and heavy metals.
1, plasticizer
Plasticizer, also known as plasticizer, is an additive used to add hard plastics to make them more elastic and durable. No.3 (PVC) is the most commonly used hard plastic as plasticizer, and all plastic containers made of PVC contain plasticizer. The 1, No.5 and No.6 plastics commonly used in take-away plastic containers are all soft plastics, which are elastic and do not need to use plasticizers.
Even the take-away plastic containers made of PVC, as long as they are qualified products produced by regular manufacturers and used correctly (for example, they are not used for high-fat foods, and the use temperature should not be too high), there will be no excessive plasticizer released into the food.
2. bisphenol A
It is said that the disposable lunch box made of plastic or resin contains an estrogen-like substance called bisphenol A, which will seep out of the lunch box after high temperature and enter the body with food. If the human body is exposed to bisphenol A for a long time, it will cause cancer.
Bisphenol A is a chemical raw material. Indeed, bisphenol A in food contact materials may be transferred to food. However, 1, 5 and 6, which are mainly used in take-away plastic containers, do not need to use bisphenol A. As for the harm of bisphenol A to human body, there is no conclusion yet. For example, regarding carcinogenicity, animal studies have not provided convincing evidence that exposure to bisphenol A is carcinogenic.
3. dioxins
It is also said that 1 (PET) plastic will release dioxins when refrigerated. Dioxins are toxic substances that can cause cancer.
However, there is no reasonable scientific evidence that 1 (PET) plastic itself contains dioxins, which will not be produced at refrigeration temperature.
4. Other chemicals
Other chemicals used to make plastics may also be released into food. For example, the plastic container made of 1 (PET) contains trace antimony.
Antimony is a heavy metal used to make PET. When the plastic container made of 1 (PET) is filled with water, the antimony contained in it can be released into the water. However, the research shows that the antimony content of PET bottled drinks is very low (far below the guidance value stipulated by the World Health Organization for drinking water quality), and it will not pose a risk to health.
In fact, China's standards for some chemicals in plastic containers are limited. For example, the antimony content in plastic containers made of 1 (PET) should be less than or equal to 0.05 mg/L.
In short, we need not worry too much about the safety of qualified disposable plastic containers produced by regular manufacturers. Of course, eating takeout too often is not a good thing, for example, it is difficult to guarantee balanced nutrition and hygiene.
Third, how to distinguish whether the takeaway plastic container is qualified?
Regarding whether the plastic containers used for take-out are qualified, we can use the methods of looking at the appearance, feeling the strength and smelling the smell. Qualified products must first have QS logo, and the surface looks smooth and transparent, without bubbles, whitening, impurities and stains. Besides, it won't feel soft, and it smells strange.
If there is a situation that "the bowl is broken before eating and smells strange", it may be an unqualified product. Of course, sometimes it is not easy to tell, so it is recommended to choose a regular fast food restaurant or restaurant to eat, because the plastic containers they use are usually of better quality.
Fourth, pay attention! Not all plastic containers are suitable for heating or holding hot food.
Do not pack high-fat foods, such as boiled fish fillets and braised eggplant in oil, in plastic containers made of No.3 (PVC) or unknown materials.
Pay attention to the use temperature of various plastic containers. For example, the plastic container made of No.6 (PS) will soften at 95℃, so don't use it to package foods with too high temperature, such as boiling soup.
Not all plastic containers are suitable for microwave heating. No.5 (PP) plastic container can withstand the high temperature of 140℃, so it can be heated in the microwave oven. However, the plastic containers made of 1 (PET) and 6 (PS) have low heat resistance, so they can neither be heated by microwave oven nor filled with too hot food. If you are not sure whether the plastic container for take-out can be heated, you can pour the food into the pot and then heat it.
Don't reuse disposable plastic takeout containers. For example, take-out boxes made of plastic. 1 (pet) and No.6 (PS) should be discarded after use and cannot be used for other foods.