How a single system can solve three key soft drinks production challenges

Handling ingredients in soft drinks preparation can give rise to several production challenges. But with the right solutions you can guarantee a trouble-free process. Our experts explain what you need to know.

Avoiding clogging and lumps

A familiar headache in beverage preparation is the tendency of some ingredients to clump together and cause blockages. Clogging typically occurs early in the process when dry ingredients are introduced to liquids to form the slurry base for the future soft drinks mix.

Lumps of sugar, citric acid or taurine that form inside packages, especially if the contents are stored for an extended period or in humid conditions, can clog intake equipment when they enter the mixing process.

One way to overcome clogging is to include a wet feeding function in your mixing setup, according to Denis Steffen, Tetra Pak Deputy Design Engineering Manager.

“Wet feeding adds liquid directly to ingredients in the hopper in a process that dissolves lumps of sugar, citric acid or taurine that may have formed prior to processing – and before the lumps can create clogging,” he says.

Wet feeding is performed by a horizontal injector, a device used to aspirate ingredients. A horizontal injector prevents clogging by creating high turbulence at the intake point.

“In a conventional injector, undissolved powder will sink to the bottom, where it congregates and creates clogging over time,” Steffen explains. “A horizontal injector, on the other hand, has a spoon-shaped gap through which the dry ingredients enter the mix. This shape guides the dry ingredients to the point of highest velocity, which stops powder from sinking.”

In our patented horizontal injector, a vital component in Tetra Pak Preparation System B, turbulence is also highest at the bottom of the pipe, which further prevents powder from sinking and forming clumps.

Managing dusty powders

Dust is a perennial hazard in any processing environment for dry ingredients. As well as being a source of product losses, it can pose a potential explosion risk if not mitigated effectively.

According to our calculations, about 0.8 percent of the powders mixed into soft drinks never make it into the final drink. They end up in the air or as residue in industry-standard extraction systems because dust is generated when you discharge a powder into a hopper.

The solution is a dust extraction system that does not treat dust as waste but instead removes it from the air through aspiration. We’ve developed an innovative, patented Extraction and Recovery System (ERS) that recovers dust for reuse. This is an option for Tetra Pak Preparation System B.

The ERS can be attached to a powder intake station to remove airborne dust generated in the feeding hopper and its surrounding environment. The dust is washed with a small amount of water into a reservoir, from where it can be recovered and returned to the recirculation stream as a water-based mixture.

“Think of it as a vacuum cleaner,” Steffen says. “An aspiration pipe extracts air from the area where the operator works, aspirates the dust, and transports it to a reservoir from where the dust is recovered and returned to the mixer.”

Our mixing technology is unique in its ability to capture and recover airborne dust with no product losses. Full hygiene is also guaranteed because the ERS is fully integrated with automated cleaning-in-place cycles. The ERS has no filters to replace and is virtually maintenance-free.

Powder with a scoop

Hydrating dry powders

The third main challenge is efficient powder hydration, also known as wetting. Hydration occurs at the start of the beverage mixing process and marks the first contact between dry ingredient and liquid product. The objective is to liquify all dry ingredients, transforming them from powder grains into liquid solution.

But some powders, especially gums, are more difficult to hydrate than others. This is because liquid may struggle to penetrate beneath the surface of a viscous gum. The result: an undesirable jelly-like undissolved mass or “fisheye” in the centre.

We perform optimal gum hydration in three steps. First, our injector creates sufficient turbulence to start the dissolving process. From there, a patented auto mixing device breaks down the gum into soluble fractions.

The auto mixing device (AMD) is a semi-static mixer that supports the mixer nozzle by breaking up gums or stabilisers before they become too viscous. It is an optional part of Tetra Pak Preparation System B.

In the soft drinks industry, gum concentrations in the final beverage usually vary from 0.2 percent to 0.4 percent. Our AMD can handle concentrations up to 1 percent at an ambient dissolving temperature (20°C) – without the need for a high shear mixing pump.

The third component for effective powder hydration is the turbulence created by the mixer nozzle. This turbulence keeps the powder grains floating inside the mixing tanks to avoid them settling on the bottom.

“All three of these steps create the turbulence needed for full and complete hydration,” Steffen says. “Producers typically approach gums by applying high shear force, but this is expensive and also very energy-intensive. Our solution requires roughly 60 percent less energy.”