A container assembly including a pouch, spout and closure is provided. When the pouch and spout are attached, one or more cavities are formed between the inner surfaces of the sidewall of the pouch and the external surface of a mounting portion of the spout. One or both of the spout and pouch include a vent which provides for fluid communication between the cavity and the ambient environment on the outside of the pouch. The vents are configured to allow for pressure equalization of the cavity relative to the outside of the pouch during sterilization of the container assembly.
