Recently, a new type of modified atmosphere packaging technology has been successfully developed in the United States. This technology is characterized by the replacement of various types of foods with different protective gases for the purpose of preserving the preservation of fresh air. It is more than a single vacuum packaging application. A wider range and better preservation results are new changes in food packaging today.

Food MAP packaging products have entered the European and American markets since the 1980s and have grown considerably. The annual growth rate has reached 25%, and the total packaging volume has exceeded 5 billion boxes. Products include fresh food (fish, meat, fruits and vegetables), cooked meat products, dairy products, baked goods and noodle foods. In China, since the beginning of the 90s of last century, the development and research of food modified atmosphere packaging processes and equipment have begun, and the conditions for commercial application have been preliminary. However, the market development is still at the initial stage. How to develop modified atmosphere packaged foods and enter the market is a problem that the majority of food companies have been concerned about.

The best quality modified atmosphere packaged foods Modified atmosphere packaging process consists of the following components: the composition and mixing ratio of protective gas and packaging materials, and the shelf life under the premise of obtaining the best package quality through testing. Modified atmosphere packaging is the preservation and preservation of protective gas by two gases or three kinds of gases in CO2, O2, and N2. The composition and mixing ratio of protective gas are determined according to the anti-corrosion characteristics of food. Fish are often contaminated with anaerobic Clostridium botulinum and produce toxins in the absence of oxygen and temperatures above 4°C. The danger is that toxins are produced before sensory degeneration and are not easily detected. Therefore, the protective atmosphere of fresh fish modified atmosphere packaging should consist of three gases: CO2, O2, and N2. Pigs, cattle, and mutton modified atmosphere packaging must both protect the color of the meat and achieve antiseptic effect. The high-oxygen environment can maintain red oxygenated myoglobin in the meat, and the protective gas should consist of more than 60% of O2 and CO2. Fresh fruit and vegetable modified atmosphere packaging reduces the metabolic activity of aerobic respiration by decreasing O2 and raising CO2 (eg, 5% O2 and 5% CO2) to delay aging and withering. Other cooked foods, baked and preserved atmospheres of protective atmospheres are composed of CO2 and N2. Most of the packaging materials for antiseptic modified atmosphere packaging require the use of a high-barrier composite packaging material to maintain the composition of the protective gas inside the package. Such as the shelf life does not have to be long, the general barrier properties of PA / PE or PET / PE can be satisfied, the shelf life of the best use of high-barrier PVDC or EVOH composite packaging materials. The packaging film of fresh fruits and vegetables acts as a gas exchange membrane. The gas composition of the package is maintained by gas exchange between the membrane and the atmosphere. The breathable PE, PP, and PVC films are commonly used. However, this film cannot meet the high breathing rate. Packaging requirements for tropical fruits and mushrooms also require the development of highly breathable films.

Cold chain for food modified atmosphere packaging Most of the modified atmosphere packaged foods are required to be stored and sold at a temperature of 0-4°C to protect food safety and quality. At present, China's cold chain of frozen foods from production, storage, transportation and sales is relatively sound, but the cold chain of low-temperature showcases, low-temperature cold storages, and low-temperature transporters adapted to atmosphere-modified packaging products at 0 to 4°C has not yet been established. Therefore, establishing a low-temperature cold chain at 0-4°C is the key to enter the market for modified atmosphere packaging products.

High-efficiency modified atmosphere packaging production equipment The main equipment for the production of food modified atmosphere packaging is the vacuum modified atmosphere packaging machine and the gas proportion mixer. At present, China's packaging manufacturing enterprises have been able to provide various types of bag or box packaging machines, automatic vacuum atmosphere packaging machines and gas proportioners for food companies. For example: Shanghai Jubei Steel Machinery Manufacturing Co., Ltd., which has developed a bag-type and box-type packaging based on the production of vacuum inflatable packaging machinery products through technical cooperation with the Shanghai University of Mechanical Engineering and Automation College and Shanghai Fisheries University Food College. A series of modified atmosphere packaging machines and gas proportioner products. The developed product has a cassette packaging ZQT-1.

D400 and MAP-200 automatic atmosphere packaging machines adopt programmable (PLC) and built-in gas mass flow rate proportioner. The packing parameters include: gas mixing ratio, gas replacement time, heat sealing temperature and time, and sealing film. Traction and mold movement time control, etc. can be automatically controlled through the LCD screen touch settings, easy to operate.
Recently, the United States has further strengthened its research on a new generation of modified atmosphere fresh food packaging systems. Ilapak's newly developed Delta 3000 LD (Long Dwell) high-speed modified atmosphere packaging machine can pre-program up to 64 production solutions to ensure quick and easy adjustment of package size. It is also characterized by the ability to precisely control the inflation, high tightness of the sealing port can be maintained for a long time, and the quality control device of the packaging bag is not on when there is no product.

At the same time, Multivac developed a new tray sealer for poultry and packaged ready-to-eat meat products. The new technology encapsulates the product in a shallow tray after being air-conditioned, and the product can achieve better visual effects while ensuring complete sealing. Rovema Packaging Machinery's range of air-conditioned flexible bags and pillow packs are suitable for coffee, breakfast cereals, baked goods and many other products. Its vertical molding/filling/vacuuming/inflating/seal system can handle liquid, viscous, granular or solid products; pillow packer speeds up to 180 packs/minute, from single servings to large food packs Can be produced.

Source: Flexible Packaging