Views: 201 Author: Site Editor Publish Time: 2021-08-27 Origin: Site
Vacuum packaging bags are often seen in daily life. Plastic pouch food packaging sterilized at high temperature not only provide a safer storage environment for food, but also ensure the safety of aluminum foil bags themselves. In addition to the technology of high-temperature cooking and sterilization, it also provides aluminum foil reflective materials that can perfectly avoid sunlight for foods that cannot be irradiated by sunlight. PA was specially added to prevent the bag from being punctured. With the vacuum food packaging poly bags, the fresh taste and color of oil products can be preserved until unsealed.
The vacuum packaging technology originated in the 1940s. Since the plastic film was successfully applied to commodity packaging in the 1950s, the technology of making vaccum seal food bags has developed rapidly. Packaging level reflects a country's scientific and technological level and wealth level to a certain extent.
1. In 1962, Ordal proposed that oxygen impermeable membrane could inhibit the growth of pathogenic microorganisms, and vaccum packed meat had a longer shelf life.
2. Baltzer believes that vacuum-packed fresh meat has a longer shelf life than aerobic-packed fresh meat. Because the total number of microorganisms increases slowly under anaerobic conditions; Decay and mucus reduction; After storage, the number of final microorganisms in vaccum sealer bag is less than that in aerobic packaging.
3. In 1970, Pierson et al. proposed that vacuum plastic packaging bags for food created an "ecosystem" for selecting the types and levels of microorganisms. In 1974, SCOPA Company first applied MAP (Modified Mosphere Package, which is a kind of package that is vacuumized first and then filled with a certain proportion of mixed gas) to package meat products.
(4) Pesis et al. (1986) put forward that vacuum polythene packaging bags are the best way to maintain the quality and hardness of fruit. It can be seen that the development and popularization of storage and preservation technology has been paid more and more attention by producers, operators and consumers.
Packaging containers are another part of the equipment needed for vacuum packaging. There are many kinds of packaging containers, such as plastics, composites composed of plastics, paper, aluminum foil and other composite materials, glass bottles, metal containers and hard plastics, etc. The selection of packaging containers should be determined according to the properties of vacuum packaged foods. Although there are many kinds of vacuum packaging containers, the most common one is heat seal plastic bags.
Vacuum packaging bags mainly include side sealing bags, tubular bags, shrink bags and cook-in bags. Side-sealed bags can not only keep food fresh, but also display goods directly on the shelves. This kind of packaging bag has good moisture-proof and airtightness. Tubular vaccum free packages are conducive to displaying the outline of products, and have good oxygen barrier, high transparency and airtightness. Shrink bags have special film structure and high barrier materials, which can prolong the shelf life of products. Cook-in bags can be stored at any temperature and have good temperature resistance.
There is no fixed shelf life for vacuum packaging bags, but it is necessary to ensure that the quality of packaging bags is good when purchasing, so as to achieve the best use effect. The shelf life of custom plastic packaging bags will be affected by pH, temperature and composition.