The thickness of plastic packaging film has an important impact on the food protection performance, mainly reflected in the following aspects:

I. Barrier properties

1. Gas barrier
   • Thicker plastic packaging films usually have better gas barrier properties for gases such as oxygen and carbon dioxide. This can slow down the oxidation rate of food and extend the shelf life of food. For example, for food rich in oil, thick packaging film can effectively prevent the infiltration of oxygen and prevent the oil from oxidizing and becoming rancid, maintaining the flavor and nutritional value of food.
   • For food that needs to maintain a certain concentration of carbon dioxide, such as carbonated beverages, thicker packaging film can reduce the escape of carbon dioxide and maintain the taste and foaming property of the beverage.
2. Moisture barrier
   • Thick packaging film can better block the entry of external moisture and prevent food from getting damp and deteriorating. For example, for dry food such as biscuits and potato chips, thick film can maintain the crisp texture of food and avoid softening due to absorbing moisture.
   • At the same time, it can also prevent the loss of internal moisture of food. For some food with high water content, such as fresh fruits and vegetables, thick film can reduce water evaporation and extend its freshness preservation period.

II. Mechanical properties

1. Strength and toughness
   • Thicker plastic packaging films usually have higher strength and toughness and can better withstand the impact and extrusion of external forces. During transportation and storage, thick film can effectively protect food from damage such as collision and extrusion.
   • For example, for fragile food such as glass bottled sauces and canned food, thick packaging film can provide additional cushioning and reduce the risk of product damage.
2. Puncture resistance
   • Thick film often has better puncture resistance and can prevent sharp objects from piercing the packaging, thereby protecting food from contamination. In the logistics process, various sharp objects such as nails and iron wires may be encountered. Thick packaging film can provide more reliable protection.

III. Heat sealing performance

1. Sealing effect
   • Appropriate increase in the thickness of plastic packaging film can improve the strength and sealing performance of heat sealing. Good sealing can prevent the invasion of air, moisture and microorganisms and ensure the safety and hygiene of food.
   • For food that needs high-temperature cooking or sterilization, the heat sealing performance of thick film is more important and can withstand high-temperature treatment without cracking or leaking.
2. Heat sealing stability
   • Thick packaging film is usually more stable during the heat sealing process and is less likely to have poor heat sealing. This can improve production efficiency and reduce the defective rate.

IV. Influences in other aspects

1. Printing suitability
   • Thicker packaging film can provide a better printing surface, making the printing pattern clearer and more vivid. This is very important for brand promotion and product display.
   • At the same time, thick film can better withstand the pressure and friction during the printing process and reduce the wear and fall off of the printing pattern.
2. Cost factor
   • Increasing the thickness of packaging film will increase the material cost. Therefore, when choosing the thickness of packaging film, it is necessary to comprehensively consider the food protection performance and cost factors and find a suitable balance.

In conclusion, the thickness of plastic packaging film has multiple impacts on food protection performance. When choosing packaging film, the appropriate thickness should be reasonably selected according to factors such as the characteristics of food, storage and transportation conditions to ensure the safety, hygiene and quality of food.