1, cooking bags. The food bag is made of flexible composite material. After the food is packaged in the bag, it is sterilized in an autoclave for a short time. The bag can be heated in boiling water before use. 2, Vacuum packaging bags. A packaging method in which the product is put into an airtight packaging container and the original air in the container is replaced with nitrogen, carbon dioxide and other gases. 3, Frozen packaging. Packaging that uses freeze-resistant and moisture-resistant packaging materials and speed technology to allow frozen contents to be stored under refrigeration for extended periods of time.