Vacuum Packaging of Food
1. Definition
Vacuum packaging: the food is packed into a packaging bag, in which the air is pumped out, and the sealing process is completed after reaching a predetermined vacuum degree.
Vacuum inflatable packaging: put the food into the packaging bag. Then pump out the air in the packaging bag to a predetermined vacuum degree. Next fill in nitrogen or other mixed gas, and then complete the sealing process.
2. Working principles
The main function of vacuum packaging is to remove oxygen in order to help prevent food deterioration, and its principle is relatively simple, because the mildew deterioration of food is mainly caused by the activities of microorganisms, most of which cannot survive (such as molds and yeasts) without oxygen. Vacuum packaging uses this principle to pump oxygen out of the packaging bags and food cells, so that the microorganisms lose their "living environment". Experiments show that when the oxygen concentration in the packaging bags is less than or equal to 1%, The growth and reproduction of microorganisms will drop sharply. When the oxygen concentration is less than or equal to 0.5%, most microorganisms will be inhibited and stop reproduction. (Note: Vacuum packaging cannot 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, irradiation sterilization, microwave sterilization, salt pickling, etc.)
In addition to inhibiting the growth and reproduction of microorganisms, another important function of vacuum deoxidization is to prevent food oxidation. Oil and fat foods contain a large number of unsaturated fatty acids, which are oxidized to make food taste worse and cause deterioration. In addition, oxidation also causes the loss of vitamins A and C, and unstable substances in food pigments are affected by oxygen, which makes the color darken. Therefore, deoxidization can effectively prevent food deterioration and maintain its color, aroma, taste and nutritional value.
The main functions of vacuum inflatable packaging are not only oxygen removal and quality preservation, but also pressure resistance, gas resistance and preservation, which can effectively keep the original color, flavor, shape and nutritional value of food for a long time. In addition, many foods are not suitable for vacuum packaging but must be vacuum inflatable packaging. For example, crisp and fragile foods, easily caked foods, easily deformed and oily foods, Foods with sharp edges and corners or high hardness will puncture the packaging bag, etc. After the food is packed in vacuum, the inflation pressure inside the packaging bag is higher 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 and printing decoration of the packaging bag.
Vacuum inflatable packaging is filled with single gas like nitrogen, carbon dioxide and oxigen or mixed gas of 2-3 kinds of them after vacuumizing. Its nitrogen is an inert gas, which plays a filling role, keeping the positive pressure inside the bag to prevent the air outside the bag from entering the bag, thus playing a protective role for food. Its carbon dioxide can be thicker than various fats or water, leading to carbonic acid with weak acidity, which has the activity of inhibiting microorganisms such as mold and putrefying bacteria. Its oxygen can inhibit the growth and reproduction of anaerobic bacteria, keep the freshness and original color of fruits and vegetables, and keep fresh meat bright red with high concentration of oxygen.
Vacuum packaging: the food is packed into a packaging bag, in which the air is pumped out, and the sealing process is completed after reaching a predetermined vacuum degree.
Vacuum inflatable packaging: put the food into the packaging bag. Then pump out the air in the packaging bag to a predetermined vacuum degree. Next fill in nitrogen or other mixed gas, and then complete the sealing process.
2. Working principles
The main function of vacuum packaging is to remove oxygen in order to help prevent food deterioration, and its principle is relatively simple, because the mildew deterioration of food is mainly caused by the activities of microorganisms, most of which cannot survive (such as molds and yeasts) without oxygen. Vacuum packaging uses this principle to pump oxygen out of the packaging bags and food cells, so that the microorganisms lose their "living environment". Experiments show that when the oxygen concentration in the packaging bags is less than or equal to 1%, The growth and reproduction of microorganisms will drop sharply. When the oxygen concentration is less than or equal to 0.5%, most microorganisms will be inhibited and stop reproduction. (Note: Vacuum packaging cannot 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, irradiation sterilization, microwave sterilization, salt pickling, etc.)
In addition to inhibiting the growth and reproduction of microorganisms, another important function of vacuum deoxidization is to prevent food oxidation. Oil and fat foods contain a large number of unsaturated fatty acids, which are oxidized to make food taste worse and cause deterioration. In addition, oxidation also causes the loss of vitamins A and C, and unstable substances in food pigments are affected by oxygen, which makes the color darken. Therefore, deoxidization can effectively prevent food deterioration and maintain its color, aroma, taste and nutritional value.
The main functions of vacuum inflatable packaging are not only oxygen removal and quality preservation, but also pressure resistance, gas resistance and preservation, which can effectively keep the original color, flavor, shape and nutritional value of food for a long time. In addition, many foods are not suitable for vacuum packaging but must be vacuum inflatable packaging. For example, crisp and fragile foods, easily caked foods, easily deformed and oily foods, Foods with sharp edges and corners or high hardness will puncture the packaging bag, etc. After the food is packed in vacuum, the inflation pressure inside the packaging bag is higher 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 and printing decoration of the packaging bag.
Vacuum inflatable packaging is filled with single gas like nitrogen, carbon dioxide and oxigen or mixed gas of 2-3 kinds of them after vacuumizing. Its nitrogen is an inert gas, which plays a filling role, keeping the positive pressure inside the bag to prevent the air outside the bag from entering the bag, thus playing a protective role for food. Its carbon dioxide can be thicker than various fats or water, leading to carbonic acid with weak acidity, which has the activity of inhibiting microorganisms such as mold and putrefying bacteria. Its oxygen can inhibit the growth and reproduction of anaerobic bacteria, keep the freshness and original color of fruits and vegetables, and keep fresh meat bright red with high concentration of oxygen.