Feb 26, 2020
The primary task of freshness preservation of fresh fruits and vegetables is to maintain the appearance, hardness, taste, and flavor of perishable fruits and vegetables. Most fresh fruits and vegetables lose their commercial value if they lose their appearance. Fresh fruits and vegetables after harvest are still living organisms, and a series of physiological changes will continue to make their unique flavor and tastefully manifest. The color, aroma, and nutritional components are more suitable for people's needs. This process is called Post-ripening stage; then, the fruits and vegetables gradually lose their original color, aroma, nutritional content and even soften and disintegrate, this is the aging stage; trying to delay the post-ripening and aging process of fresh fruits and vegetables is to maintain the original quality process as much as possible, this time This process is called the shelf life. Reducing waste and loss is one of the research directions of the flexible packaging industry.
Modified Atmosphere Packaging
Modified atmosphere film packaging is one of the most commonly used fruit and vegetable preservation technologies at home and abroad. According to the physiological characteristics of fruits and vegetables, this technology replaces the original atmosphere in the package with mixed gas (oxygen, carbon dioxide, nitrogen, etc.) with a certain composition ratio, and maintains the best air permeability and moisture permeability by selecting a suitable film.
However, at present, MAP in the domestic market mostly uses film packaging fruits and vegetables made of materials such as polypropylene or polyethylene. The permeability of the film is not high and it is difficult to maintain a healthy breathing rate. The water vapor in the package is easily saturated and condenses into water droplets. It is easy to cause the growth of harmful microorganisms and accelerate the decay of fruits and vegetables.
Laser micro-perforated fresh-keeping film packaging
In order to solve this problem, micro-perforated fresh-keeping film packaging technology came into being. This process can combine the transpiration rate and respiration rate of agricultural products to "tailor" the optimal pore size and number of holes.
At present, the main punching methods in the industry are mechanical punching (such as punching, hot-needle processing, and electrical discharge piercing) and laser punching. Laser drilling is the earliest practical laser processing technology, and it is also one of the main application areas of laser processing.
Compared with other drilling methods, laser drilling can easily achieve the micro-aperture requirements (generally, the micro-hole fresh-keeping film needs a hole diameter between 50 and 200 microns), high laser processing accuracy, large working area, easy monitoring and adjustment, and no direct contact Film body (clean and pollution-free), more suitable for food packaging processing.
The laser process is very flexible, can be easily integrated into the packaging machine, the hole size is monitored and adjusted in real-time, and the hole spacing can be easily changed through programming to optimize production cycles.
Laser micro-perforated packaging advantages
1. Precisely control the size and number of holes to achieve the best air permeability and moisture permeability.
2. Physically prolong the storage time, the nutritional composition and color taste of fruits and vegetables have not been damaged.
3. The aperture is small, the edges are neat and difficult to crack.
4. Anti-fog control, to achieve the best transparency under temperature changes.
Laser microperforated film industry prospects
There are many types of laser choices, but because of the high pulse energy and output power of the CO2 laser; low operating voltage, safe application; high optical quality, good stability, uniform discharge, suitable for large area operations, etc., very suitable for micro-perforation Flexible packaging.
With its high performance, high reliability and low cost, the new cutting-edge carbon dioxide lasers that KING’S laser has produced are ideal for laser marking, engraving and cutting systems. As a low-cost OEM laser, UL RF-excited CO2 lasers are especially suitable for laser equipment manufacturers, such as laser cutting machines, laser engraving machines, and laser marking machine manufacturers.