MAP packaging machine technology developing trend

Modified atmosphere packaging is a new type of food preservation technology. It uses protective mixed gas (usually CO2, N2, O2) to replace the air in the package, and uses the different effects of various protective gases to suppress most of the food deterioration. Microorganisms grow and reproduce, and reduce the breathing rate of active foods (fruits and vegetables and other plant foods), thereby keeping food fresh and prolonging its freshness.

In recent years, some mathematical models about the relationship between the gas composition in the modified atmosphere packaging and the respiration rate of fruits and vegetables, as well as the relationship between the respiration rate and the air permeability of plastic films, have been continuously proposed.

Plastic fresh-keeping film is currently the most commonly used packaging material for fresh fruit and vegetable packaging. The transparency of the film allows you to see the condition of the packaged product at a glance; moisturizing can reduce the moisture loss of the product and increase the freshness; breathability can play a role in spontaneous air conditioning and prolong freshness Time; airtightness can protect the product from contamination; the low price also makes the film's application prospects very broad. There have been ordinary cling films, silicon window air-regulating cling films, microporous cling films, edible cling films, and anti-corrosion films. Fog function cling film, antibacterial cling film, etc.

The gas replacement device is the core component of the modified atmosphere packaging machine. The gas replacement methods mainly include gas vacuum replacement and flushing. The main principle of vacuum replacement is to suck the original gas into a vacuum and then fill the mixed gas. Its performance will directly affect the replacement accuracy. It will indirectly affect the quality of product packaging and shelf life. In order to improve the replacement accuracy, relevant experts have done relevant research on the optimization design and flow field simulation of the cassette and bag type gas replacement device, and analyzed the changes in gas flow rate and pressure, as well as filling and discharging. The pore structure layout and other effects on the gas diffusion replacement rate and replacement time, by changing or optimizing the replacement structure to obtain a higher replacement rate, and in order to obtain a higher gas replacement rate, the loss of replacement gas is also more serious.

The gas proportioning mixer is the core component to realize the gas proportion adjustment and control, and it is also the key technology to realize the modified atmosphere packaging. After the compressed gas is decompressed by the pressure reducing valve, it enters the gas mixing chamber, and then introduces the inflatable packaging machine for inflation Packaging and mixing methods mainly include isometric gas ratio mixing method (isovolume method), isobaric gas ratio mixing method (isobarometric method), constant volume and pressure gas ratio mixing method (constant volume and pressure method), throttling gas ratio Mixing method (throttle method), time gas proportional mixing method and mass flow method 6 types. Mass flow proportional mixers in foreign countries such as Japan, the United States, etc., although the gas mixing accuracy is high, the product price is also very high. Constant volume constant pressure method GM type gas proportional mixer, its mixing accuracy has reached ±1%.