Is there a trend toward food packaging that is more sustainable and more environmentally friendly than conventional packaging materials?
Yes and no.
Cost savings, public image and individual values are some of the factors in decisions to simplify the packaging of foods and beverages. Customer requirements also enter into the equation. Unsurprisingly, companies pulling in one direction can be pushed in another. Two cases in point:
Diamant is a German sugar company that is serving as the pilot application for a specialized paper that can be used as a substitute for polymer film on a high-speed, vertical form/fill/seal (VFFS) machine. Diamant sees the paper alternative as a way to burnish its sustainability image with European consumers. In doing so, it became the first food company to apply a solution that was a decade in the making.
According to Marcus Velezmoro of Bosch Packaging (www.boschpackaging.com) in Waiblingen, Germany, that’s how long the collaboration between the machine builder and BillerudKorsnas AB, a supplier of biodegradable packaging materials, took to bear fruit. “It was unprecedented to co-develop a machine with a material supplier,” notes the sales manager for Bosch’s VFFS ZAP portfolio. In-house efforts to modify a VFFS machine to handle both paper and plastic were going nowhere.
The same could be said of the go-it-alone approach at Solna, Sweden-based BillerudKorsnas (www.billerudkorsnas.com). Even a machine-and-material partnership proved challenging. “We destroyed millions of bags on the prototype,” laments sales director Ole Paulussen.
Stretchability—in technical parlance, the amount of energy packaging material can absorb before rupturing—is not a characteristic of kraft paper. A recipe of 100 percent Nordic virgin fiber produced paper material with half the stretching ability of polypropylene film but 10 times that have conventional paper while retaining enough strength to withstand a 6-ft. drop.
Multilayer film includes a sealant layer that is activated by the VFFS’s jaws when the package is formed. A specialized sealant needs to be applied to monolayer paper in order to close the package. HB Fuller was asked to develop an adhesive that could be applied to specific areas of the paper while on the machine’s web.
Applying that sealant proved as challenging as BillerudKorsnas’s search for stretchable wood fibers. Bosch engineers developed an accessory module inspired by cartoning machines, which use a single nozzle to apply adhesive. Shorthanded as ZAP, the module uses multiple, programmable, flexible nozzles to apply precise amounts of the sealant. “The physics are the same as a cartoner,” says Velezmoro, “but in micron-thin quantities.” Heat from the sealing jaws activate the adhesive.
The result is packaging material that costs less than polymer, even if a finish is added for high-quality printing. The reason: less waste, because adhesives are applied only where needed, not throughout the film. “When you consider all the substrates in plastic, the cost of producing a biodegradable film is not justifiable,” he explains.
“Biodegradable paper turns out to be less expensive than polymer.”
The ZAP module is bolted on to Bosch’s SVC 2520, a continuous motion VFFS that fills and forms bags up to 2.2 lbs/1kg. The machine can output 80 bags per minute with conventional film. The speed drops to 65 bpm with paper, a rate food manufacturers indicated would be acceptable for packaging that meets consumer expectations for sustainable packaging, Velezmoro says.
The VFFS used by Diamant is a prototype machine that only fabricates paper pouches. Assuming sufficient demand from packagers, Bosch will make the ZAP module a bolt-on option that allows the SVC 2520 to run both paper and plastic film.
PET vs. recycled glass
Sustainable packaging never was a question at Once Again Nut Butter Collective Inc. (www.onceagainnutbutter.com), a Nunda, N.Y., natural and organic processor of peanut butter, seed butters and other spreadables. Environmentally sound practices are part of the employee-owned company’s ethos, and that extends to the 16-oz. recycled glass jars it uses.
However, bowing to market pressures, the Rochester area company expects to add PET containers as an option for private-label buyers who want to reduce shipping costs.
Once Again was founded in 1976 by two University of Wisconsin-Madison graduates with a passion for community involvement and organizing co-operative ventures. Like modern day Johnny Appleseeds, the couple made their way east to Rochester, leaving in their wake a string of co-ops. When they began roasting nuts and packing pails with nut butter in their basement, they were, once again, creating a co-op.