Active packaging technology application trend

At present, most of the food packaging in supermarkets can only serve as food instructions and prevent food contamination. It is generally believed that as long as the packaged food is within the shelf life, it should be safe, but it is not. In order to ensure food safety and prevent consumers from mistakenly eating spoiled foods, scientists have developed new packaging technologies that can indicate whether foods are deteriorating and packaging technologies that extend the shelf life of foods. These technologies are collectively referred to as "active packaging technologies" or "smart packaging technologies." . Food packaging researchers have found that some materials can absorb oxygen in packaging bags; some materials can interact with gases produced when food spoils, changing color; some materials change color when temperature changes. If such materials are used to package foods, it will help prevent food from oxidizing and deteriorating, or provide consumers with more information on the safety of foods.

Since these active material packages have the function of demonstrating food safety, many companies are cooperating in various forms to study such "active packaging." French “different” supermarket chains are using a type of packaging technology called “time temperature indication” on many fresh foods, abbreviated as TTI. It's actually a label that shows how long food has been stored at a certain temperature. This kind of label is like a shooting target. There are many rings of transparent rings. The center ring contains a chemical substance. This chemical will polymerize with time and temperature and change from transparent to black. If the packaged food is kept at a low temperature, the polymerization of the chemical will be very slow. Once the temperature increases, the polymerization will accelerate and the chemical will change from transparent to black. As the bacteria on foods increase with temperature and time, the degree of darkening of chemicals becomes more and more serious. When the inner ring turns black, it means that the food is no longer fresh. Consumers can use this change in the color of the label to determine if the food has been stored at high temperatures for a long time. The use of such labels to package foods allows consumers to make targeted choices, not to mistakenly select spoiled foods, and to avoid disputes caused by food spoilage.

Another food safety indicator packaging technology that the researchers studied is a kind of plastic wafer that is doped with dyes. It interacts with the gas released from the food in the packaging bag to show if the meat and vegetables are deteriorating. After the plastic piece is put into the food packaging bag, if the food in the packaging bag is rotted, gas will be released and the plastic piece will change color. Consumers can know if the food is deteriorating based on the color of the plastic sheet.

The above smart packaging technology can only show consumers whether the food is deteriorating, while another smart packaging technology can control the environment inside the packaging bag and extend the food preservation period. Different fruits and vegetables need to be kept at a certain concentration of oxygen and carbon dioxide, and such oxygen and carbon dioxide concentrations are difficult to control in sealed bags. Because when the temperature is high, the fruits or vegetables in the package will consume more oxygen and release more carbon dioxide. Therefore, if no adjustment is made, the preservation period of food is bound to be affected. To solve this problem, a company in Menlo Park, Calif., is working on a packaging film called Intelimer. When the temperature changes, the membrane will change its permeability so that different foods are kept at the optimal oxygen and carbon dioxide concentration ratio.

Another way to slow down the rate of deterioration of foods is to use an oxygen scavenger to remove oxygen and control the air inside the package to avoid oxidative deterioration of the food. At present, a common method is to put a small sachet containing iron powder in the food packaging bag, and consume the oxygen in the packaging bag through the iron powder. However, this method has obvious deficiencies because the “inedible” warning signs on small sachets are likely to cause consumers to resent. For this reason, a sealed gas company in New Jersey, USA, is producing a bag material that can remove oxygen itself. This material has an inner layer of oxidizable polymer that traps and consumes oxygen inside the package like iron powder.

In addition to the above two smart packaging technologies, there are some more unique smart packaging technologies, such as smart beer sealed can technology. When this smart beer can is unscrewed, the beer can be automatically cooled down to 16.7°C in 3 minutes, allowing people to drink refreshing cold beer. The reason why the beer can achieve such an effect is that the beer can adopts a unique intelligent packaging technology. This beer can consists of two parts, the upper one is filled with beer, the outer beer layer is covered with a hydrogel, and the lower part is composed of a vacuum layer, a desiccant and a heat absorbent layer. When the beer can is unscrewed, the pressure in the can drops, causing the water in the can to evaporate and the beer temperature to drop. Evaporated water is absorbed by the desiccant while the heat absorber absorbs heat. Because such beer cans can be kept fresh and iced, they become the famous smart packaging in the current supermarket.

Intelligent packaging technology can facilitate consumers to choose foods that are safe and secure, can extend the shelf life of foods, and is conducive to the preservation and transportation of foods. It has broad market prospects. In particular, consumers are more in need of smart packaging technology if the market supervision mechanism is not sound and counterfeit products are still very rampant. Researchers predict that in the near future, the number of bags produced with smart packaging technology will account for 20%-40% of the total number of food packaging bags.