Liquid nitrogen extends shelf life because it displaces oxygen from the package headspace. The doser injects a drop of LN2 into the container before or after filling, ahead of capping; the drop evaporates, the nitrogen volume expands roughly 700 times, and the gas pushes air out of the neck. Without oxygen, product oxidation slows down.
Oxygen in the package headspace triggers oxidation. Sensitive products — juices, tea, wine, beer, dairy, vegetable oils — lose taste, aroma and colour. The less oxygen remains in the container after capping, the longer the product keeps its original properties.
Yes. Nitrogen is the main component of air (78%), chemically inert, colourless, odourless and tasteless, and does not change the product composition. In the EU, nitrogen is authorised as packaging gas and propellant E941 (Regulation (EC) No 1333/2008). In the USA, the FDA classifies nitrogen as GRAS (21 CFR 184.1540). Production requirement: ventilation of the filling area and oxygen monitoring in the room.
A gas tunnel flushes containers with gaseous nitrogen. A doser delivers nitrogen precisely into each container in the liquid phase. According to VBS Europe, this reduces nitrogen consumption compared with gas tunnels. In addition, dosing creates positive pressure in the container — an effect that flushing does not provide.
Yes. Both pre-filling inerting (pre-purge) and headspace inerting after filling, ahead of capping, are used.
The result depends on the product, container and initial oxygen content. The effect for a specific product is determined by trials — including on your line (individually, on request).
Sources: Regulation (EC) No 1333/2008; 21 CFR 184.1540; VBS Europe; Vacuum Barrier Corporation.
