Flexible multilayer laminates may have an improved integrated, one-way pressure-release valve for use in a sealed container for packing gas-producing products. The pressure-release valve is partly disconnected from the rest of the laminate, forming an inflatable outlet tube with at least one large outlet opening and lifting off from the laminate under increased pressure in the pack. The one-way pressure-release valve allows for pressure-release at low minimum opening pressure in a reliable and reproducible way.