Working principle of food vacuum packaging machine
The main function of the food vacuum packaging machine is to remove oxygen to help prevent food spoilage. The principle is relatively simple. The mildew and spoilage of food is mainly caused by the activities of microorganisms, and the survival of most microorganisms (such as molds and yeasts) is Oxygen is needed, and vacuum packaging uses this principle to extract the oxygen in the packaging bag and food cells, so that the microorganisms lose their living environment. Experiments have proved that when the oxygen concentration in the packaging bag is 1%, the growth and reproduction speed of microorganisms will drop sharply. When the oxygen concentration is -0.5%, most microorganisms will be inhibited and stop reproducing. (Note: Vacuum packaging machine vacuum packaging vacuum packaging can not inhibit the reproduction of anaerobic bacteria and food deterioration and discoloration caused by enzyme reaction, so it needs to be combined with other auxiliary methods, such as refrigeration, quick freezing, dehydration, high temperature sterilization, and irradiation sterilization. , Microwave sterilization, salting, etc.) In addition to inhibiting the growth and reproduction of microorganisms, vacuum deoxygenation has another important function to prevent food oxidation. Because fats and oils contain a large amount of unsaturated fatty acids, they are oxidized by the action of oxygen. Food tastes bad and spoiled. In addition, oxidation also causes the loss of vitamin A and C, and the unstable substances in food pigments are affected by oxygen to darken the color. Therefore, deoxygenation can effectively prevent food from spoiling. In addition to the oxygen-removing and quality-preserving functions of vacuum packaging, vacuum inflatable packaging also has the functions of anti-compression, gas barrier, and preservation, which can more effectively maintain the original color, aroma, taste, shape and nutrition of the food for a long time. value.
There are also many foods that are not suitable for vacuum packaging by vacuum packaging machines and must be vacuum-filled packaging. Such as crunchy and fragile foods, foods that are easy to agglomerate, foods that are easy to deform and run out of oil, foods with sharp edges or corners or high hardness that will pierce the packaging bag, etc. After the food is vacuum-inflated and packaged, the inflation pressure inside the packaging bag is stronger than the atmospheric pressure outside the packaging bag, which can effectively prevent the food from being crushed and deformed under pressure without affecting the appearance of the packaging bag and the printing performance. The vacuum inflatable package is filled with a single gas such as nitrogen, carbon dioxide, and oxygen or a mixed gas of two or three gases after being vacuumed. Among them, nitrogen is an inert gas, which plays a filling role and keeps positive pressure inside the bag to prevent air outside the bag from entering the bag and play a protective role for food. Carbon dioxide can be dissolved in all kinds of fats or water, and it is introduced into weakly acidic carbonic acid, which has the activity of inhibiting molds, spoilage bacteria and other microorganisms. Oxygen can inhibit the growth and reproduction of anaerobic bacteria, and maintain the freshness and color of fruits and vegetables. High concentration of oxygen can make fresh meat maintain its bright red color.
