If there is no plastic packaging food system will be hit
作者:
來源:
日期:
2016-04-01
人氣:
19848
【字體:
T
T 】
With the further development of the plastics industry, plastic packaging and food has become an indispensable important member of integrated food system. If you remove the plastic packaging, food will be difficult for long preservation, it is difficult for consumers for thousands of miles delicacy.
The plastic density is small, lightweight, transparent or opaque, easy to process, as long as the replacement of the mold to obtain the containers of different varieties, easy to form the mass production. But it also exists many problems, such as: plastic at high temperature easy deformation surface hardness low easy to wear; in oxygen and light heat oxygen will brittle degradation; poor electrical conductivity, easy to produce electrostatic accumulation and pollution link and so on. But despite this, it still gives us life has brought great convenience.
If there is no food plastic packaging system will hit
Alan Brody (AaronBrody) is a food packaging consultant, associate professor of food science at the University of Georgia, according to him, the food packaging plastic revolution began in the 1960's. So the selection of plastic, because it is lighter than the glass, than paper firmly, but also cheaper. But Brody also pointed out: "there is no universal plastic". Many bags we touch, are made of plastic food packaging and the combination of different types of.
We can see the life form of every kind of plastic packaging, common to several:
A bag of chips
It is the main component of a called "oriented polypropylene plastic". Brody explained: "that is a good moistureproof layer." In the chip package, moisture is the key, because the chips absorb moisture they will begin to deteriorate. Wet chips is not love." In order to further strengthen, many bags of potato chips in the inner layer of a thin layer of aluminum.
Name of commodity and nutritional information are printed on the outer layer, and between the two outer layers also with a layer of polyethylene. Brody also revealed that before sealing packaging bags, most companies will inject nitrogen in them. "This prevents the chips from crushing." Oxygen will make the fat oxidation, chips produced in the smell of nitrogen would not cause any damage to the taste of chemical reaction.
Food companies often spend a lot of time designing packaging, the purpose is best to save every product they sell. This is also the practice of the army. Prior to this report, the army has used a packaging to extend the shelf life of the sandwich to two years.
Salad packing bag
And a bag of chips, is ready to eat vegetable salad packing bag is made of polypropylene production and is also injected into the bag of nitrogen. And chips is different, is a little salad leaves need to breathe oxygen, which is why the bag with a small hole in the salad. Brody pointed out: "the small hole so that oxygen can enter, carbon dioxide can be discharged." He added that the inside of these bags often has a thin layer of anti fog layer, so it will not happen condensation, but also allows consumers to see the beautiful green leaves."
Ice cream bucket
In making a lot of plastic packaging, manufacturers are not only about how to isolate the air, but also how to save water. Brody, for example, is very important in the packaging of ice cream. A bucket of ice cream must be able to easily opening and closing, but it must also have a tight seal, water locking, so as to maintain a smooth mouthfeel.
In the refrigerator to preserve, and sometimes sublimation, that is, the water directly from the solid into a gaseous phenomenon. "Once the water is lost, it cannot be recovered, and the ice cream will be lost if the ice cream is lost." Brody said.
Of course, as food expert Herbert. Stone said that, even after a variety of research and development, the majority of plastic packaging is still not in the extreme environment to save food. Stone is a food industry consultant, former chairman of the Institute of food is technician.
Stone pointed out: "the food companies in the use of plastic containers, must ensure that they do not change the taste of food." He added that is not an inert material plastic, it can react with other chemicals. And many glass or metal products, it also allows air to pass through.
Plastic bottle
Have you ever put a plastic bottle too long too hot in the car? It tastes mostly is weird. But the reason you think different: This is not because the chemicals in plastics into the water.
Stone explained that the trace of the air can penetrate the plastic, and when the temperature rises, the air movement will accelerate. The heat will accelerate chemical reactions. When the bottle of chemical substances react with each other, or with the material in the external environment react, bottle of water will drink a smell.
A bottle of soda water in the hot car, which will quickly escape from the bottle carbonate. "The rest is not a bubble of soda." Stone said, "plastic really convenient, but it is not a panacea."
In addition to its limitation in technology, all plastic packaging will we use today produces a lot of rubbish. In 2012 alone, the United States had produced 14 million tons of plastic garbage bags and containers. Biodegradable plastics are not easily, so sometimes into the ocean, which not only hurt the sea creatures, even contaminated seafood.
Although many kinds of plastics can be recycled, the beautiful packaging contains multi-layer plastic is very difficult because of the cycle.