| 摘要 |
The outer bag is of foil material, possibly in the form of a hose, form which the package is produced by welding or closure in some other wway at its ends. The foil material is barrier-forming, i.e. impermeable to gas. Inside the outer bag are a number of inner packages used to contain fresh food such as meat chops, vegetables, fish, etc., such inner packages being composed of a basic tray of cardboard or aluminium foil, and a cover of fluid-tight, but non-barrier-forming foil material permeable to gas. - The whole packaging arrangement, at the time of formation, is filled with a protective gas of suitable type e.g. a mixt. comprising approximately 20 per cent by vol. of oxygen, and 80 per cent by vol. of carbon dioxide or nitrogen. |
