The definition of vacuum packaging
Vacuum packaging will be food into the bag, extract the air in the bag, to achieve a predetermined vacuum, complete the sealing process. The vacuum inflatable package packs the food into the bag, pulls the air out of the bag to reach a predetermined vacuum level, fills it with nitrogen or other mixtures, and then completes the sealing process.
Vacuum packaging principle, vacuum packaging refers to the extraction of all the air in the package and with the oxygen penetration rate is very low packaging materials, so that the outside oxygen can not penetrate into, reducing the rate of oxidation of fresh meat, acidity to ensure the freshness of fresh meat. Vacuum-packed fresh meat can be stored at 0±1 degrees C for 14 to 20d.
Vacuum packaging itself than tray packaging shelf life extended by 5 to 7d, but after vacuum packaging, due to the blocking of oxygen, the general meat will be dark red, damage to the appearance. However, if the packaging is removed, the cooling meat is returned to a bright red color with oxygen, so vacuum packaging is generally used for long storage time and requires high-quality hotels and some hypermarkets.
The materials used in vacuum packaging, in addition to anti-oxygen perimeter and good shrinkage of polydechloride (PVDC), there are polyester, polyamide; Or nylon, polyester film and polyethylene multi-layer materials. Among them, polydichloride prevents oxygen and water vapor permeability for all kinds of membranes, but the biggest disadvantage is not heat sealing. Polyester has a strong tension strength, softness; Nylon to prevent oxygen penetration rate is good, heat, cold resistance is also good, mechanical is also very strong, but the water vapor pass rate is large, and expensive, so many in the form of multi-layer composite as fresh meat vacuum packaging materials.
The role of vacuum packaging inhibits the growth of microorganisms and avoids external pollution; Slowing down the oxidation rate of fat in meat also inhibits enzyme activity. Reduce water loss and maintain the weight of the product; Packaging is beautiful, intuitive, enhance the desire to buy, easy to carry.
