Analysis of the preservation principle of food vacuum packaging machine

Analysis of the principle of food vacuum packaging machine preservation

An important part of the food vacuum packaging machine is the removal of oxygen. The main function of vacuum packaging is to remove oxygen, which is beneficial to prevent food spoilage. The principle is also relatively simple, because the deterioration of food mold is mainly caused by the activity of microorganisms, and the survival of most microorganisms (such as mold and yeast) is needed. Oxygen, and vacuum packaging is the use of this principle, the oxygen in the package and food cells are removed, so that the microbes lose the "environment of survival." The experiment proves that when the oxygen concentration in the package is ≤1%, the growth and reproduction speed of the microorganisms drops sharply, the oxygen concentration is ≤0.5%, and most microorganisms will be inhibited and stop breeding. (Note: Vacuum packaging can not inhibit the deterioration and discoloration of food caused by anaerobic bacteria reproduction and enzyme reaction, so it needs to be combined with other auxiliary methods, such as refrigeration, quick freezing, dehydration, high temperature sterilization, irradiation sterilization, microwave sterilization, salt Pickled and so on.

In addition to inhibiting the growth and reproduction of microorganisms, vacuum deoxidation is another important function to prevent oxidation of foods. Oils and fats contain a large amount of unsaturated fatty acids, which are oxidized by the action of oxygen to make foods taste and deteriorate. In addition, oxidation also causes loss of vitamin A and vitamin C, and unstable substances in the food coloring matter are subjected to oxygen to darken the color. Therefore, oxygen scavenging can effectively prevent food from spoiling and maintain its color, aroma, taste and nutritional value. The radish strip vacuum packaging machine has the same effect as long as it can reach a certain degree of vacuum.

Another important part of the food vacuum packaging machine is inflation. The main function of vacuum air-packing is not only the anti-oxidation and quality-preserving functions of vacuum packaging, but also the functions of anti-pressure, gas-blocking and fresh-keeping. It can effectively maintain the original color, fragrance, taste and shape of food for a long time. Nutritional value. In addition, there are many foods that are not suitable for vacuum packaging, but must be vacuum-filled. Such as crispy and fragile food, easy to agglomerate food, easy to deform oily food, food with sharp edges or high hardness will pierce the bag. After the food is vacuum-inflated and packaged by the food vacuum packaging machine, the inflation pressure in the packaging bag is stronger than the atmospheric pressure outside the packaging bag, which can effectively prevent the food from being crushed and deformed without affecting the appearance and printing decoration of the packaging bag.

The vacuum inflated package is filled with a single gas of nitrogen, carbon dioxide, oxygen or a mixture of two or three gases after vacuum. Nitrogen is an inert gas that acts as a filling to maintain a positive pressure inside the bag to prevent air outside the bag from entering the bag and to protect the food. Carbon oxide gas can be dissolved in various types of fat or water to form weakly acidic carbonic acid, and has the activity of inhibiting microorganisms such as mold and spoilage bacteria. Oxygen inhibits the growth and reproduction of anaerobic bacteria, keeps the freshness and color of fruits and vegetables, and high-concentration oxygen keeps fresh meats bright red.