A valve structure includes a housing having an interior chamber, a first conduit connecting the interior chamber with a cooking chamber of a cooking device and having a first discharge cross-section, a second conduit connecting the interior chamber with the outside environment and having a second discharge cross-section, and at least one valve seat within the interior chamber having at least one valve seat opening which cooperates with at least one valve disc. The at least one valve disc moves between a closed position on the valve seat opening, and an open position spaced apart from the valve seat opening by changes in pressure in the cooking chamber. The valve operates to allow bidirectional flow of fluid to relieve over pressure and underpressure conditions, and enables automatic balancing of low pressure or vacuum in the cooking chamber.