Do I Need a Nitrogen Purge System for My Packaging Line?
Nitrogen purge systems are not a staple of every packaging line, at least not at the same level as a filling machine, capping machine or power conveyors, which are found on nearly every automated system. At LPS, we often get queries asking what the nitrogen purge system does and if it should be included on a packaging line. Whether or not a nitrogen purge system is a fundamental or necessary part of a packaging system depends in some part on the industry being served and the products being packaged.
Nitrogen purge systems are most often used to rid head space of oxygen just before a bottle or container is capped or sealed. In some cases, the purge may also be used to strengthen brittle bottles as well. However, the end goal of most nitrogen purge systems is to remove the oxygen and the negative effects that the oxygen may have over time on the product. For example, imagine a packager in the Food and Beverage Industry. These products will almost always include an expiration date, or a date at which the product may no longer be fit for consumption. In many cases, the effect of oxygen on these products is what leads to the quick decay of the product. Removing the oxygen via a nitrogen purge system can prolong the shelf life of the product, extending the expiration date and reducing waste or product spoilage. In addition to prolonging the shelf life, removing the oxygen from a container may also help to maintain the natural texture, color and flavor of a product. So in general terms, the nitogen purge can extend the useful life of many different products. This extends to any product, not just foods and beverages and not just liquids, on which oxygen may have a negative effect.
So how do the systems work? They are actually fairly simple machines. The purge system may attach to a power conveyor just before an automatic capping machine, inserting the nitrogen to displace oxygen just before the bottle or container is sealed. The quick seal after the purge helps to ensure that minimal oxygen creeps back into the head space before the container is closed. The purge system can also be manufactured as a stand alone machine or as a portable machine that can roll up to the power conveyor system. Different applications may call for different configurations as well, meaning the nitrogen purge system can be custom built with a single head, multiple heads, enclosures or any other option necessary to meet the needs of the individual packager.
So to answer the question of whether or not a nitrogen purge system is necessary, in most cases the packager must ask what affect, if any, oxygen has on the product being prepared. As noted above, some applications may use either liquid or gas nitrogen for other reasons, but more times than not, extended shelf life is the main goal. If you are unsure of whether your line will benefit from the addition of such a system, LPS Packaging Specialists are always available to discuss options, products and projects.