PRESS RELEASE: The flexible Stand Up Pouch: an ideal package style for snacks
Snack products (nuts, dried fruits, cookies etc…) are one of the most popular products in today’s supermarkets, and represent a strong selling item in the store. They can be strategically positioned in the store for quick point of purchase, like end of aisle or check out register to engage impulse buying habits by consumers.
The type and design of the package is very important to attract the attention of the consumer. The Stand Up Pouch is used more frequently for packaging of snacks due to its functionality as well as its attractiveness and platform for different design formats. By “standing out” more on the shelf, the product better differentiates itself from the competition on the shelf, and provides the consumer at home with benefit of a stable storage feature, factors that contribute to why consumers opt more and more to purchase snack brands in this package style.
In order to maintain and guarantee product freshness and safety, the product should be packed on a high quality filling machine. Freshness and quality can be enhanced with use of a modified atmosphere system, utilizing nitrogen to lower the amount of residual oxygen inside the pouch, yet without changing any flavor or texture of the product.
As a general rule, a multihead combination weigh scale system is used to weigh fill the product as accurately as possible and to reduce product give away.
Once the product is released from the weigh scale it is transitioned through transfer funnels where nitrogen can be flushed as product enters the pouch, and an expanding duck bill style funnel helps to open the pouch wide enough to ensure product enters pouch without jamming or interference. This duck bill also flushes nitrogen into the pouch to lower the residual oxygen inside the package.
Once filled, the pouch indexes to the pouch closing and sealing stations. In the pouch closing or stretching station, additional nitrogen can be injected into the pouch to evacuate more oxygen from the pouch headspace.
The package film material used is typically a multi-layer laminate of barrier materials with a film thickness specific to each application.
For example, for a one time use salty snack pouch, the film thickness is usually in region of 60 microns thick and could be a PET 12 micron / PE 50 micron laminate. The film should not be too thick or it will add to the overall package cost, as well as create a need to increase seal temperature and pressure in the machine.
For larger size pouches with larger amounts of product inside, a recloseable zipper can be added to the pouch so that it can be used for multi-use occasions and also to help preserve the product quality inside the pouch.
In such cases, it might be recommended to increase film thickness, especially the PE layer while maintaining the same thickness of the external PET layer. Some film structure examples might be PET 12 micron / PE 70 micron, or a PET 12 micron / PE 100 micron, depending on the product type.
An aluminum layer can also be added, typically 9 microns thick, for a 3 layer film. A combination of PET12/ALU9/PE80 is a common film structure that ensures package integrity and product safety. In cases where cost reduction is important, the aluminum film layer can be substituted by a metallized film between the PET outer layer and PE inner sealant layer.
Technological innovations in more complex films have allowed improvements to the time, pressure and temperature functions, allowing sealing systems to meet or exceed quality requirements.
Snack applications typically have a high content of salt. For such applications, it is advisable that the machine construction design be made of corrosion resistant materials such as stainless steel AISI 304 and AISI 316, titanium and even certain plastics that are saline resistant. Without such a construction, the machine will not withstand long term use or rigorous cleaning procedures.
Machinery that is entirely constructed using servo drive control mechanisms with built in monitoring programs, allows a far greater control of each machine function due to each motion having its own independently controlled axis.
Independent control of each axis (as opposed to a single line axis for all functions) allows flexibility to adjust each critical machine function, such as sealing time, sealing pressure, filling time, simply by adjusting the design of the electronic cams. This offers a more user friendly way to improve the pouch forming and filling process, and ultimately result in a higher level of guarantee to produce a quality product.
BOSSAR PACKAGING S.A.