| 摘要 |
<p>Packaging material for products possessing microbial flora consists of a perforated sheet suppor, associated, on at least one of its faces, with a heat-sealable plastic film which is highly permeable to oxygen but only weakly permeable to moisture. The support is pref. microperforated, and is a cellulosic film, a metal sheet, a metallised sheet of film, or a thermoplastic film. The heat-sealable plastic film is pref. made from polyolefin or its copolymers or ionomers. The packing is esp. useful or cheese whose quality depends on the maintenance of living microbial flora. It can also be used for foodstuffs where quality or appearance depends on a continuous supply of oxygen. Vacuum packing under materials impermeable to gas is prejudicial to microbial flora, but the new material maintains them in a living state whilst the beneficial aspects of vacuum packing are retained.</p> |
