Can The Plastic Wrap Be Heated In A Microwave Oven?

　　Can the plastic wrap be heated in a microwave oven?

　　Many people know that mineral water bottles are not resistant to high temperatures, so don't put mineral water in the car in summer. Did you know that it's not good to wrap food in plastic wrap and put it in the microwave to heat it?

　　The material of the plastic wrap

　　Most of the qualified household food wraps on the market are low-density polyethylene (LDPE), referred to as PE plastic wrap. PE cling film is characterized by safety, non-toxicity, strong ductility, and certain water permeability, so it can be in direct contact with food at room temperature. Household plastic wrap sold in supermarkets or e-commerce channels is generally made of PE.

　　Another type of plastic wrap used in large quantities uses polyvinyl chloride (PVC) materials. PVC is characterized by low cost and high transparency. But because it is relatively hard, to be suitable for the scene of plastic wrap, plasticizers are generally added, which are carcinogens with health risks. PVC cling film often appears in vegetable markets, small supermarkets, and other places where a large amount of use and cost saving is required. It is only suitable for packaging raw food that needs to be cleaned again.

　　Another type of plastic wrap is polyvinylidene chloride (PVDC). This material has better preservation time and moisture retention, high self-adhesiveness, and strong insulation, and is safe and non-toxic, so it is suitable for wrapping deli meat and oily food. However, the price of PVDC is also higher, so it is relatively rare, and most of them are imported products.

　　It is difficult to tell the difference between these three films with the naked eye and feel, and can only rely on product packaging and purchase channels.

　　heat resistance of plastic

　　So, what is the heat resistance of the above three plastics?

　　PE: When it exceeds 110 degrees, it begins to shrink and deform, and its physical properties are greatly weakened, and even broken.

　　PVC: The softening point is 80-85 degrees, the decomposition point is 130 degrees, and the plasticizer in it begins to precipitate when it exceeds 60 degrees, so in fact, PVC cling film is risky as long as it is heated.

　　PVDC: The melting point is between 198 degrees and 205 degrees, and there is no serious problem before 140 degrees. Among the three, it is resistant to high temperatures.

　　For plastics, there are three more important temperatures: softening point, melting point, and decomposition point.

　　The softening point is the starting point at which heat begins to deform, and the melting point is the temperature at which the plastic begins to liquefy.

　　The first two are mainly physical changes, and when the decomposition point is reached, the plastic begins to undergo chemical changes, and the large molecules fall apart and crack into small molecules.

　　microwave heating temperature

　　Microwaves heat food by vibrating polar molecules (water or oil) in food to achieve the purpose of heating. Because the boiling point of water is 100 degrees under normal conditions, most of the time microwave heating is only 100 degrees.

　　But if there is oil in the food because the oil has a higher boiling point, it may exceed 100 degrees when heated, and the highest may even reach 250 degrees.

　　At this time, if the plastic wrap is next to the food, it may not be heat-resistant and affect food safety. In addition, most of the molecules of the precipitates in the plastic have an affinity with oil, and the precipitates come into contact with the oil and enter the food during the heating process, which is also a potentially unsafe factor.

　　In fact, among daily plastic products, only No. 5 plastic PP has better thermal stability, and it will not deform or melt when heated below 140 degrees. PP plastic lunch boxes are generally marked with the words "microwave oven safe".

　　Conclusion: For your health, please do not put plastic wrap in the microwave oven.

　　Tips for Microwaving Plastic Products

　　After consulting many sources, we have compiled more suggestions on the use of microwave ovens.

　　1. Only put plastic products labeled "Microwave Safe"/"Microwaveable"

　　2. Even plastic wrap marked "microwave safe" should not come into contact with food. Use a deep bowl or plate with some clearance above the food.

　　3. In case the plastic is found to be melted, deformed, or even burned, please discard it together with the food.

　　4. Do not put the following items in the microwave oven:

　　Various plastic bags

　　Disposable paper cup

　　Tetra Pak milk or drink

　　Film-coated paper packaging (commonly used for cakes and bread)

　　Aluminum foil food packaging