The Duravant family of operating companies serve the food processing, packaging and material handling segments.
5 Tricks for Packaging Sticky Products
Some products – such as nuts, chips, and other free-flowing foods – move very easily through a production process.
But dealing with sticky products is an entirely different scenario.
Sticky products may want to stick to various contact surfaces within machinery – or to each other – which creates potential obstacles to ensuring that weighing, filling, and packaging processes move smoothly. This is where nVenia’s applications engineering team becomes a critical part of the process when choosing packaging machinery.
While there are many ways to handle sticky products, here are 5 tips we typically build into our processes:
1. Use Dimpled – Not Flat – Contact Surfaces
Whenever dealing with an overly sticky product, nVenia's applications team recommends using dimpled, rather than flat surfaces on the multi-head weigher, bucket elevator, incline conveyor, and other contact surfaces.
The dimpled texture creates less surface area for the products to stick to throughout the packaging process. Depending on how well the product flows, it may also be advisable to make additional modifications to the multi-head scale, such as tilted feed pans or a spinning cone accessory.
2. For Accuracy, Choose Multi-Head Weighers Over Linear
In general, multi-head weighers are fast and more accurate than linear scales. But when dealing with stickier product, like gummy vitamins or cannabis edibles, the potential for clumping creates an opportunity for overweights in a linear scale.
In a linear weigher, product is metered out at a higher rate of speed for most of the target weight, and then dribbled in for the remaining portion. That faster “bulk” fill accounts for anywhere between 70-90 percent of the target weight, depending on the fill amount and the flow characteristics of the product.
The potential for an overweight is greater when clumps are present in the dribble portion of the scale. If a product intended to be 5 oz. sits at 4.9 oz, and a large clump of product is the next piece to drop, the package will likely be over.
With a multi-head scale, the amount of each product contained in the weigh buckets is combined to reach the final weight – regardless of whether the product in each bucket is made up of single pieces or one large clump.
3. Flow Agents
With many products, such as cheese shreds or crumbles, even a dimpled surface is not enough to keep product moving, which is when flow agents can be introduced into the process. These agents – generally cellulose-based – allow products to move through scales and other equipment without sticking.
4. Climate Control is Crucial
The moisture content inherent in sticky products makes climate control in the packaging facility/room a critical factor to ensure the product moves smoothly through the process.
The stickiness of gummy products is often reduced when they are refrigerated, which may allow the product to be weighed and packaging more quickly.
When dealing with pastes and products like peanut butter, the opposite is true. Heating up the product allows it to flow and be pumped more smoothly.
Humidity is also a factor with many products. When dealing with products such as granola, the moisture content of the air can react with honey or other sticky ingredients, creating the potential for clumping.
5. Metered Filling Reduces Clumping
It is always important to ensure that the forming tube/container opening is large enough to accommodate any individual piece of the product.
But if multiple pieces clump together, it creates an added potential hurdle in the filling process.
One way to overcome that, as nVenia’s OHLSON Brand does in our gummy packaging systems, is to use vibration to break up the clumps and meter out the filling process to ensure a large clump does not get stuck in a container opening.
The obvious counter-effect of metering out the filling process is that speed can go down. But by filling multiple containers at one time, the overall output speed of the system can still be maintained.