A venting assembly for a closed container having a lid and a container portion with a neck and a rim. The assembly comprises a venting unit having a substantially rigid ring having a lid-interfacing surface and a resilient annular valve member having a one-way valve disposed at the inner wall of the neck. The assembly further comprises at least one air passageway leading from the ambient atmosphere to the one-way valve member and a fixing mechanism adapted to prevent planar movement between the venting unit and the container.
