Vacuum Packaging Machine Overview and Principle

Vacuum, this term is translated from Latin vacuo, its meaning is nothingness. In fact, vacuum should be understood as a space where the gas is relatively thin. In the specified space, gas states below one atmosphere are collectively referred to as vacuum. The degree of gas thinning in a vacuum state is called the degree of vacuum, which is usually expressed as a pressure value. Therefore, the vacuum packaging is not actually completely vacuum, and the degree of vacuum in the food container packaged using the vacuum packaging technique is usually 600-1333 Pa. Therefore, vacuum packaging is also called decompression packaging or exhaust packaging.

Semi-automatic baler technology originated in the 1940s. In 1950, polyester polyethylene plastic film was successfully used for vacuum packaging. Since then, vacuum packaging has been rapidly developed. China's vacuum packaging technology was developed in the early 1980s, and vacuum inflatable packaging technology began to be used in small quantities in the early 1990s. With the promotion of small packaging and the development of supermarkets, its application scope has become more and more extensive. Some will gradually replace hard packaging and the outlook is very promising.

The main role of the semi-automatic baler is to remove oxygen and help prevent food spoilage. Its principle is also relatively simple. The deterioration of food is mainly caused by the activity of microorganisms. Most microorganisms (such as the yeast yeasts need oxygen , And vacuum packaging is the use of this principle, the oxygen inside the packaging bag and food cells removed, so that microorganisms lose their living environment. Experiments show that: when the oxygen concentration in the bag ≤ 1%, the growth and reproduction rate of microorganisms When the oxygen concentration is ≤ 0.5%, most microorganisms will be inhibited and stop reproducing.(Note: Vacuum packaging does not inhibit the growth of anaerobic bacteria and the deterioration and discoloration of foods caused by enzyme reactions, so it needs to be supplemented with other methods. Combinations, such as cold storage, quick freezing, dehydration, high temperature sterilization, irradiation sterilization, microwave sterilization, salting, etc.) In addition to inhibiting the growth and reproduction of microorganisms, vacuum deoxidation is another important function to prevent food oxidation due to oils and fats. Foods contain a large amount of unsaturated fatty acids, which are oxidized by the action of oxygen, causing the food to taste and spoil. In addition, Of further loss of vitamin A and C, the food coloring substance unstable by the action of oxygen, so that dark color. Therefore, oxygen can effectively prevent food spoilage.

In addition to the oxygen scavenging and quality assurance functions of vacuum packaging, vacuum inflatable packaging mainly includes the functions of pressure resistance, gas barrier, and freshness preservation, and can effectively maintain the original color, fragrance, taste, shape and nutrition of foods for a long time. value.