Pouch Filling

Pouches have a lot of things going for them. They take up less space than rigid containers, both before they’re filled and when they’re discarded (which adds to their environmental appeal). They’re often less expensive, on a per-unit basis, than rigid containers. And in many applications, especially for beverages, they have a novelty that can create considerable shelf appeal.

But one of their biggest drawbacks is product security, in several forms: opening them safely and easily, dispensing products (especially liquid products) from them accurately and reclosing them.

Fitments, with screw tops or other closures, are a way to overcome this disadvantage. Until recently, filling pouches with fitments was one of the toughest challenges in using pouches. But alternatives in machinery have made filling pouches with fitments much more reliable, in terms of both handling and ultimate product quality.

Manufacturers can fill pouches that have fitments through a number of different methods:

• put the fitment on the corner of the pouch and fill alongside it (the most common filling method in North America);

• fill through the pre-placed fitment;

• fill with a wide filling tube through a large gap in the pre-formed pouch, then the fitment is applied and the bag is sealed.

The ultimate goal is to have zero head space, meaning no excess room that could collect or cultivate gases or chemicals that could contaminate the product. And a tamper-evident feature on the fitment is something consumers demand. The biggest challenge is to connect laminated film to a fitment with no gap.

Several innovations in filling pouches with fitments have emerged in the last several years:

• Three-way technology for sealing pouches that use fitments with carrying rails. The pouches are loaded onto a carrying rail and delivered to the filling machine. They’re then filled while they’re still flat. Excess product on the outside of the pouch and fitment can literally be washed off.

• A pasteurized/aseptic packaging system that seals the fitment to the pouch by heating, pressurizing, then cooling, each in one-second intervals.

• A double-head fill-seal system that offers a convenient alternative for companies looking into concentrates and other thick liquids. Each pack sits within a puck as it moves across the linear production line, making the filling operation as clean as possible.

• A pouch that is divided into two or three components, each with a separate ingredient of a product, such as a cocktail with liquor and mixer. The consumer squeezes the pouch to rupture the internal seals and mix the product, then dispenses the mixed product through a central fitment. Filling is done through the fitment for one component, and through the flexible top prior to sealing for the other chamber(s).

• A vertical form-fill-seal machine for bag-in-box applications that eliminates the manufacturing step of pre-formed bags. This accommodates a small fitment opening, further reducing the possibility of contamination. The headspace can be flushed continuously with an inert gas like nitrogen, and air can be evacuated much more efficiently-important considerations for a product like wine. F&BP