Plastic bag factory teaches you how to identify quality and choose plastic bags suitable for food

About the quality identification method:

1. The outer packaging of food plastic bags must be marked with the name of the factory, the address of the factory, the name of the product, and the words "for food" should be clearly marked. Products are accompanied by a product inspection certificate after leaving the factory.

For example, some black plastic bags used to store fish, shrimp and other aquatic products or meat in vegetable markets were originally used to store garbage, and consumers should avoid using them. It also depends on whether there are impurities in the plastic bag. Put the plastic bag in the sun or light to see if there are black spots and holes. Plastic bags with impurities must be made of waste plastics as raw materials.

2. Smell the plastic bag to see if there is any odor, whether it makes people feel sick. Qualified plastic bags should be odorless, and unqualified plastic bags will have various flavors due to the use of additives.

3. Qualified plastic bags have a certain strength and will not break as soon as they are torn; unqualified plastic bags are often poor in strength and easy to break due to the addition of impurities.

4. When the qualified plastic bag shakes, it will make a crisp sound; the unqualified plastic bag is often a "humming" muffled sound.

Plastic bags contain less hot and oily food. Of course, if you're not sure if a plastic bag is safe, avoiding it for overheated or greasy foods is one way to reduce the harm.

Unsafe plastic bags, which mainly contain harmful substances such as dyes and heavy metals. Oily foods such as meat, fish, and fried dough sticks contain oil that is actually a solvent, which can precipitate harmful substances in plastic bags; high temperature will soften the plastic, which can also promote the precipitation of harmful substances, leading to poisoning.

Therefore, it is relatively safe to pack vegetables or frozen food at room temperature. Of course, try not to use plastic bags to store food. You can bring your own basket or cloth bag when shopping for groceries; if you have to use it, you should also take out the food in the plastic bag as soon as possible after returning home.

Buy plastic bags suitable for food:

1. The outer packaging of food plastic bags must be marked in Chinese, with the name of the factory, the address of the factory, and the name of the product, and the words "for food" should be clearly marked. Products are accompanied by a product inspection certificate after leaving the factory.

2. Plastic packaging bags for food are odorless and odorless when leaving the factory, and plastic packaging bags with special odor cannot be used for food packaging.

3. Colored plastic packaging bags cannot be used for food packaging.

4. Try to use materials that are not coated or plated. In modern packaging design, in order to make the packaging more beautiful and corrosion-resistant, a large number of materials with plating are used. This not only brings difficulties to the recycling and reuse of materials after the products are scrapped, but most of the coatings themselves are toxic. If people eat these packaged foods, it will cause great harm to people's bodies. In addition, the coating and plating process also brings great pollution to the environment. For example, the paint volatilizes toxic solvent gas, and the waste liquid and waste residue pollution containing heavy metals such as chromium are generated during electroplating.

5. When purchasing food, choose green packaging materials, preferably original paper packaging or biodegradable plastics.

In daily life, what needs to be distinguished is PVC and PE plastic films (bags). Simple methods:

1. Touch method

It feels lubricated by hand, and the surface seems to be coated with a layer of wax (chemically called wax feeling). This is a non-toxic polyethylene film bag, while the polyvinyl chloride film is a little sticky to the touch./

2. Shake method Shake by hand, the sound is brittle, and the quality is easy to float is the polyethylene film bag. And the low sound of shaking hands is the polyvinyl chloride film bag.

3. Combustion method of plastic bag factory

It is flammable in case of fire, the flame is yellow, paraffin-like oil drips when burning, and there is gas when the candle burns. It is a non-toxic polyethylene film bag. If it is not easy to burn, it will be extinguished after leaving the fire, the flame is green, and it is a polyvinyl chloride film bag.

4. Immersion method

Immerse the plastic bag in water, press it into the water by hand, the polyethylene that can surface is polyethylene, and the one that sinks to the bottom is polyvinyl chloride (the density of polyethylene is less than that of water, and the density of polyvinyl chloride is greater than that of water; 0.92g/cm3 and 1.4g/cm3).

It is also possible to take a copper wire, burn it red in the fire, and then contact the copper wire with the plastic film used for the test to produce chemical changes, and then put the copper wire dipped in the plastic component back into the flame. At this time, you need to observe carefully. If there is a colorful and dazzling green flame, it means that this plastic material contains chlorine and belongs to the PVC material.