Add money. Roast chicken vacuum packaging bag is to add money, such as Jingning roast chicken (45.00 yuan only) Jingning roast chicken (vacuum packaging) (47.00 yuan only). Vacuum packaging, also known as decompression packaging, is the packaging container of all the air out of the seal, to maintain the bag in a highly decompressed state, the air is scarce equivalent to the effect of low oxygen, so that microorganisms do not have the conditions for survival in order to achieve the purpose of food freshness, no disease and decay occurs.