| 摘要 |
The invention relates to a method for heat-sealing a tray with gaseous internal atmosphere, of the type in which the open tray 10, containing the foodstuffs 11 to be packaged, is placed in a leaktight box 16, a vacuum is created in the box and in the tray to a predetermined residual pressure, a gaseous mixture intended to increase the shelf-life of the foodstuffs is injected into the box, the tray is then closed by means of a protective-covering film 12 made from plastic material, which is heat-sealed on a peripheral return 14 formed on the edge of the tray. According to the invention, the injection of the gaseous mixture is interrupted when the pressure inside the leaktight box and thus the tray has reached a predetermined value, advantageously close to atmospheric pressure. <IMAGE>
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