Provided is a storage container that includes a body that defines an interior of the storage container, and a bag contained within the interior of the storage container. The bag is constructed of an elastomer, includes an opening, and defines a bag interior configured to contain a material. The storage container further includes a material valve assembly coupled to a portion of the body. The material valve assembly is coupled to the bag and configured to selectively provide fluid communication between the bag interior and an external environment of the storage container.

A dispensing system for a liquid container including a cap configured to be mounted to a spout connected to a liquid container. The system includes a flexible valve positioned in the cap to be in contact with the liquid contents of the liquid container and a retaining ring connected to the cap to secure the flexible valve to the cap. The cap includes at least one channel defined by a projection configured to receive the tab of a connecting member and secure the connecting member to the cap by securing the tab in the channel under the projection.