Reasonable selection of packaging materials to ensure the safety of frozen food

Frozen food refers to the food raw materials of qualified quality after proper processing, frozen at -30 °C, and stored and circulated at -18 °C or lower temperature after packaging. The biggest feature of frozen food is that it completely maintains the original quality of the food in a low temperature environment, and preserves the nutrients of the food to the greatest extent without the help of any preservatives or additives. However, in the process of packaging, transportation, and storage of frozen food, it is often inevitable to face some unsafe environments and human factors, such as temperature fluctuations, shocks, vibrations, and pressures in the process of transfer and handling. Therefore, the most important part of the safety and quality assurance of frozen food, in addition to the technical control of the production enterprise, the control of environmental conditions in the logistics links such as transportation and storage, is the selection of packaging materials.

At present, the common frozen food packaging bags on the market mostly use the following material structures:

（1）PET/PE

This structure is more common in quick-frozen food packaging, with good moisture-proof, cold-resistant, low-temperature heat sealing performance, and relatively low cost.

（2）BOPP/PE、BOPP/CPP

This kind of structure is moisture-proof, cold-resistant, and low-temperature heat sealing tensile strength is high, and the cost is relatively economical. Among them, the appearance and feel of BOPP/PE structure bags are better than those of PET/PE structure, which can improve the product grade.

（3）PET/VMPET/CPE、BOPP/VMPET/CPE

Due to the existence of the aluminized layer, this type of structure has exquisite surface printing, but the low-temperature heat sealing performance is slightly worse and the cost is higher, so the usage rate is relatively low.

（4）NY/PE、PET/NY/LLDPE、PET/NY/AL/PE、NY/PE

The packaging of this type of structure is freeze-resistant, impact-resistant, and has good puncture resistance due to the presence of the NY layer, but the cost is relatively high, and it is generally used to package angular or heavier products.