In addition to ensuring food safety, plastic food packaging bags are also an important means to ensure the sensory quality of food, such as color, aroma, and taste. In the modern developed commercial field, food packaging also plays an important role in promoting food. Therefore, as a plastic packaging bag for food, at least the following requirements should be met:

1. Strength requirements:

Due to the fact that food needs to go through circulation processes such as stacking, transportation, and storage before it can reach consumers after packaging is completed, it is required that food packaging has a certain strength and will not be damaged during circulation.

2. Impedance requirements:

The barrier requirements of food plastic packaging bags are determined by the characteristics of the food itself, and different foods have different requirements for their packaging barrier characteristics. The barrier properties of food plastic packaging bags ensure that various bacteria, dust, light, gases, moisture, etc. in the external environment cannot enter the food inside the packaging. On the other hand, they ensure that the moisture, oil, aromatic ingredients, and other essential ingredients for food quality do not penetrate outward, thus achieving the goal of ensuring that packaged food does not deteriorate. Some foods also require packaging materials to have selectivity in gas barrier, such as fruit and vegetable preservation packaging. By controlling the pore size of the material, O2 and CO2 can be selectively permeated, thereby controlling the respiratory intensity of the packaged food and achieving the purpose of fruit and vegetable preservation.

3. Safety and Health:

The packaging materials for food not only have the necessary barrier properties, but also ensure the safety, non-toxic, and non volatile matter production of the packaging materials themselves, which requires the packaging materials to have stable organizational components. In addition, during the implementation of the packaging process, there will be no substances or chemical components that react with food ingredients. During storage and transfer, chemical changes will not occur due to changes in climate and normal environmental factors.

4. Temperature resistance requirements:

Most food processing processes require heat treatment, some of which are packaged and subjected to high-temperature treatment, such as canned food and steamed small foods, some are hot filled, such as many hot canned beverages, and many foods have a long shelf life, such as reaching or exceeding one year. This type of food stored at room temperature will inevitably go through hot summers and need to be continuously stored above 300C, all of which require the packaging of the food to have a certain degree of temperature resistance. The requirements for temperature resistance vary with different food and processing techniques.

5. Light avoidance requirements:

Light is very detrimental to the maintenance of food quality and nutrition. Especially the exposure to ultraviolet radiation can cause the oxidation of fats and oils in food, leading to rancidity, and the oxidation of natural pigments in food, resulting in changes in the color of the food. This can promote the loss of vitamin B and vitamin C in the food. In addition, light can also cause physical and chemical changes that are not conducive to maintaining food quality, such as amino acid decomposition and sugar melting. Therefore, for good food packaging, light avoidance is also important.

6. Safety requirements:

Due to the fact that food is a daily consumer product that needs to go through the circulation process to reach consumers, it is required that food packaging should be suitable for placement, handling, display, and easy to purchase. It should not have injurious edges or burrs, and should be equipped with specialized handheld devices to facilitate purchase. It should also be considered that even if the packaging is opened incorrectly, it will not cause harm to consumers.

7. Promotional requirements:

Promotion is one of the important functions of food packaging. Promotional requirements require food packaging materials to have characteristics such as easy printing, easy styling, easy coloring, and light weight. In this regard, plastics undoubtedly have unique advantages.

8. Convenience requirements:

Convenient packaging is often an important reason for consumers to choose a certain food. The convenience of packaging includes the convenience of use, such as the packaging of seasonings and the convenience of form, such as the newly launched milk tablets (dried milk powder); Convenient places, such as travel and leisure food that needs to be light in weight, small in size, and easy to open for consumption; Requirements for convenient carrying, measurement, operation, and selection.