Analysis of the development trend of the hottest m

Analysis of the development trend of modified atmosphere packaging (III)

all kinds of vacuum packaging machines with inflation function in China can be used for modified atmosphere packaging. However, except intubation vacuum packaging machines, other types of vacuum inflation packaging machines cannot be directly filled into plastic bags during inflation packaging, and they can be inflated after being emptied every time, resulting in high cost due to high air consumption. For example, the inflation function of single chamber or double chamber vacuum packaging machines cannot be used directly due to high air consumption, The design needs to be improved to play the function of filling gas

4. The air supply mode of modified atmosphere packaging

food should achieve the purpose of keeping fresh, and it has high requirements for the atmosphere and environment. Therefore, no matter what kind of modified atmosphere packaging machine, it is first required to be able to accurately configure the gas. There are two ways to provide mixed gas to modified atmosphere packaging machines abroad. One is centralized gas supply, that is, the gas is distributed according to the user's requirements in the way of gas supply station, which should cut 6 joints for re inspection; If one joint still fails to meet the requirements in the re inspection results, the accuracy of gas distribution can reach 1%. The other is to use the gas proportioning device online with the modified thermoforming vacuum packaging machine, vertical or horizontal automatic bag making and packaging, and the gas distribution ratio can be changed arbitrarily according to the requirements of packaging products. For this type of machine, the gas proportional mixing device is a very important component. The gas proportion mixing control device in DQ and HQ modified atmosphere packaging machines developed by China is integrated with other control devices, and the program operation of air extraction, inflation and heat sealing is controlled by single chip microcomputer. There are also various gas distribution devices, which are introduced in many journals. As for the gas source, the preparation of carbon dioxide gas is relatively common. Here we need to mention the preparation of nitrogen. In the past, it was usually refined by using the waste gas left by the oxygen plant. At present, there is a new nitrogen generator abroad - pressure swing adsorption nitrogen generator. The principle of this generator is to use the different diffusion rates of oxygen and nitrogen in carbon molecular sieve to achieve the purpose of separation, that is, the diffusion rate of oxygen in carbon molecular sieve is greater than that of nitrogen, so that carbon molecular sieve preferentially adsorbs oxygen, and most of nitrogen is enriched in the non adsorbed phase, so that oxygen and nitrogen are separated. The machine directly uses air as raw material, changes the pressure, and can also obtain gases of different concentrations, which is conducive to automation. Therefore, it has a good development prospect

5. Means and methods of quality control of modified atmosphere packaging

modified atmosphere packaging needs to ensure that the filled gas meets the required standard proportion. The current detection method is to take random samples, that is, take out a certain number of packaged products within a specified period of time, and use an air analyzer to analyze whether the gas in it reaches the proportion. This is very cumbersome and has a certain delay. If the detection is too frequent, it will inevitably cost a lot of manpower and material resources. If the detection time is too long, once problems are found, many products may be scrapped. At present, the latest detection method is detection, that is, the gas analyzer is installed at the place where the package is sealed for sampling. If the gas atmosphere does not meet the requirements, the controller will alarm and stop the process until it is corrected and meets the requirements. The outstanding feature of this method is that it can detect the errors in the gas mixing proportion in time, and save manpower. If it is used together, it can be programmed into this mode medium range controller, which can automatically adjust when the gas mixing proportion is out of balance, which can greatly improve the productivity

leakage detection of packaging is also a very important link. Leakage of packaging will affect the preservation of food, especially oxygen-containing packaging. Once leakage occurs, food will deteriorate. Now the commonly used leak detection method is to put the packaging bag into the water, squeeze the bag, or vacuum on the water surface to see if there are blisters. The disadvantages of this method are obvious. Not only is it cumbersome, composite polyurethane adhesive is developing rapidly as an environmental protection material, but also it can only be sampled for testing. There is no very advanced method for this, but some data show that a leak detection method called tracer gas method is being studied and practiced. Tracer gas method refers to installing a gas sensor in a specific vacuum state to detect the package to be tested. It is said that this method can be connected with the packaging production line for automatic detection, which is expected to be applied in the near future

conclusion

modified atmosphere packaging technology can not only prolong the storage time of food, but also well preserve the original flavor of food. Therefore, the modified atmosphere packaging of food can extend the shelf life of food products, make food sell out of season, and increase the added value of food. Combined with traditional cooking technology, the development of instant food with modified atmosphere packaging is suitable for people with a fast pace of life. Therefore, the modified atmosphere fresh-keeping packaging technology will be greatly valued and utilized in this century, such as the pressure light energy of the valve core, which can be ground to smooth with bud paste