Some food are not suitable for vacuum packaging so they have to be packaged in dunnage bag, for example, moist food, Fragile food, easy yielding food, fried food, high hardness food, food with sharp edges and so on. The advantage of dunnage bag is ont only keeping low-oxygen conditions, but also resist compression，retain freshness to prolong the shelf life of goods and maintain the original color, smell, taste, shape and nutritional value of food.