Due to the different physiological characteristics of food itself and the different conditions encountered in the transportation and marketing of food, the requirements for packaging have changed a lot. There are many factors to be considered when using the skills of food air bag packaging. There are many kinds of air bag fresh-keeping gases, different products use different fresh-keeping gases, and the gas share is also different. The most commonly used air bag packaging is nitrogen, carbon dioxide, oxygen or their mixture of gases.

1: Nitrogen is stable in nature. Nitrogen is generally used to sweep away oxygen, and then slow down the oxidation and respiration of food. Nitrogen also has a certain inhibition on the growth of bacteria. In addition, nitrogen is basically insoluble in water and oil. The adsorption of food on nitrogen is very small. When packaging, nitrogen will not gradually shrink due to the absorption of gas.

2: Carbon dioxide is one of the most important gases in air conditioning packaging. It can inhibit the growth of bacteria and fungi. When it is used for fruit and vegetable packaging, carbon dioxide has the function of strengthening oxygen reduction and reducing respiratory intensity. However, when using carbon dioxide, it is necessary to pay attention to the high solubility of carbon dioxide to water and oil. The dissolved carbonic acid will change the pH value and taste of food. When carbon dioxide is dissolved together, the amount of gas in the package will be reduced, which will simply cause the food package to shrink and not be full, and affect the appearance of food. It is necessary to consider storage temperature, moisture content of food, variety and quantity of microorganism and other factors in the application of carbon dioxide in air-conditioned packaging.