Modified Atmosphere Packaging (MAP) (Modified Atmosphere Packaging), also known as gas replacement packaging, is widely used in the preservation packaging of fresh food (fish, meat, fruits and vegetables), cooked food and grilled food. Compared with frozen packaged foods, modified atmosphere packaging for foods has high freshness preservation quality, which can maintain the original juice, original taste and original color of foods, and meets the requirements of ready-to-eat or cooking in kitchen engineering.