The headspace in containers for liquid and viscous products may originally be oxygen-free, but as the content is depleted, air is taken in and the oxygen concentration rises.
Bag-in-bottle solutions have separated content from the atmosphere by placing it in a flaccid inner container surrounded by a semi-rigid, flexible outer compartment containing air.
• The present invention reverses the roles of the two compartments: the product is in an outer, semi-rigid, flexible container made of an oxygen barrier, from which it is dispensed through a one-way valve with outward direction; air is sucked into a centrally positioned, distensible subcompartment through a one-way valve with inward direction. This subcompartment contains an oxygen scavenger, so the content is bounded on one side by an oxygen barrier and on the other side by a thin-walled compartment containing an oxygen-free atmosphere.
• Dispensing of the content is prompt and controlled up to the end, without positioning and bashing, because there is no headspace.
• The content is visible over the entire outer aspect of the device, when it is transparent. In the prior art, the content was in an unsightly bag inside the air-filled outer container, which was therefore made opaque.
The device can be used both for food and non-food products, the oxygen scavenger being incorporated only when required, or replaced by another agent, e.g., a desiccant or an antiseptic.