Speakers discussed micro-foamed layers in cast coextruded film, water-quenched coextruded blown film, high-pressure pasteurization and co-injection molding.
Bill Cunningham, business leader of packaging – North America for DuPont’s Packaging and Industrial Polymers (P&IP) group, and David Dean, P&IP technology manager, led the session with an overview of the issues driving packaging innovation. Those issues include global food waste and food insecurity, sustainability of materials and processes, providing a positive consumer experience, and cost containment.
David Luttenberger, global packaging director at research firm Mintel, then dove deeper into current packaging trends.
Packaging superheroes
On the issue of fighting global food waste, which is valued at nearly $1trn annually, Luttenberger said packaging companies have an opportunity to be — and be viewed by consumers as — superheroes.
“We know that packaging combats food waste by protecting product safety and extending shelf life,” he said. “The challenge is to educate consumers that packaging adds value, not waste, and that food is actually a greater contributor to the waste stream than packaging.”
Luttenberger said the entire packaging value chain — from resin suppliers to converters, to brand owners and retailers — needs to look beyond “sustainability” to the broader scope of environmental responsibility. The latter is not so much about next-generation packaging materials as it is about optimizing resources and exploiting existing infrastructures. Suppliers are looking at existing technologies and identifying new ways to apply them, Luttenberger said.
“It’s not just about downgauging, lightweighting and [other methods of] material reduction,” he added. “The industry is also adopting a circular model, in which regenerative technologies give packaging a second or alternative life.”
Connecting consumers with packaging
Luttenberger also discussed smart technologies and active packaging elements, such as radio frequency ID (RFID) tags and quick response (QR) codes. He indicated the potential of those technologies (and others) is only beginning to be tapped.
“Consumers are looking for packaging to add more functionality in their daily lives and engage them at the point of sale, rather than simply entertaining them,” he said.
Another trend Luttenberger identified is a shift from “disruptive” packaging to “solutions-based” packaging. “A great example of this is AirCarbon — a California company [Newlight Technologies] has developed a process for pulling CO2 out of the air and making plastic packaging from it,” he said.
Foam meets function
Jim Stobie, CEO of Macro Engineering & Technology, discussed his firm’s technology for making microfoamed barrier cast film for use in food and beverage packaging.
Individual layer foaming is achieved by injecting an inert gas through a feed-block that distributes each layer of the melt flow, he said. Foaming produces layers that maintain rigidity yet use less resin (about 20-50% less, depending on the specific application) and are lighter in weight than conventional film layers.
Stobie gave the example of combining three different substrates to create a cap liner for a bottle with a rigid plastic body and a flexible cap. The liner incorporated a gas-foamed layer, a barrier layer, and a polyethylene (PE) layer.
“Our technology enabled us to produce the substrate in a single extrusion,” he added. “The resulting liner provided a gas barrier and a compression seal for the finished package.”
Lighten up
For packaging suppliers, the benefits of foaming individual layers within a multi-layer film structure include a reduced carbon footprint, reduced resin volume, good reclosability, and the ability to eliminate volatile blowing agents from the packaging process, he added.
“For consumers, the primary benefit is enhanced shelf life of the product.”
Macro’s foaming technology, introduced earlier this year, allows cast barrier films to be used in thermoformed trays, insulated pouches, value-added lamination materials and stiffer, glossy films for shelf appeal.
HPP horizons
Errol Raghubeer, senior VP, HPP science and technology, Avure Technologies, spoke on future horizons for high pressure pasteurization (HPP, also known as high pressure processing).
Raghubeer said US food companies began showing interest in HPP in 2003, after significant outbreaks of Listeria monocytogenes infections linked to ready-to-eat meats and fresh guacamole spurred the industry to seek more effective means of controlling the pathogen.
He referred to the interim final rule, “Control of Listeria monocytogenes in Ready-to-Eat Meat and Poultry Products,” that USDA’s Food Safety and Inspection Service (FSIS) published on June 6, 2003. HPP was listed in the Compliance Guidelines as an Alternative 1 post-lethality treatment.
On the up and up
Since 2003, adoption of HPP has grown steadily, with a 25% increase from 2010 to 2014, Raghubeer said. To highlight HPP’s advantages, he provided a comparison of HPP vs. heat pasteurization, pulsed electric field (PEF), ultraviolet (UV), and electron beam (EB) processing methods (see table below).
Of those five methods, he said, HPP is the only one that is suitable for use in all of the following product categories: 1) juices and other beverages, 2) ready-to-eat meats, 3) wet salads, dips, and condiments, 4) ready meals, and 5) raw proteins.
Raghubeer added unlike heat pasteurization, HPP has no effect on the nutrition or flavor profile of foods. “In fact, food processed with HPP has almost the same attributes as fresh food,” he said.
To date, more than 300 HPP systems have been installed worldwide, Raghubeer said. Thus, HPP trails heat pasteurization in terms of commercial applications, but is much more widely used than PEF, UV, and EB methods.
Seafood stumbling blocks
Despite its advantages, “there are some [food] categories where HPP can’t penetrate,” Raghubeer acknowledged. “For instance, Clostridium botulinum and other spore-forming bacteria are not affected by HPP.”
Seafood packaging is a particular challenge, he said.
“In the absence of heat pasteurization, FDA requires seafood packaging to have a minimum oxygen transmission rate (OTR) of 10,000cc/m2/24 hrs to prevent C. botulinum from growing and producing toxins,” he said.
“You can’t use micro-perforated materials, and the [currently available] films that meet the 10,000 OTR requirement are too thin,” he added. “We need our packaging suppliers to develop a sturdier material with a similar OTR to thinner films.”
Session moderator David Dean, technology manager for DuPont’s Packaging and Industrial Polymers (P&IP) group, responded to Raghubeer’s challenge before introducing the next speaker.
“This is a great example of why we host these kinds of seminars — there’s always something more to learn,” Dean said. “I wasn’t aware of the 10,000 OTR requirement before, so now I have something to take back to my [R&D] team.”
Thirst for clarity
David Kerfoot, VP of sales and marketing for Brampton Engineering, discussed his firm’s water-quenched coextruded blown film, called AquaFrost. The technology reduces the formation of wrinkles in the film, which results in exceptional clarity, Kerfoot said.
The AquaFrost system uses chilled water instead of air to quickly quench downward blown polymer. The film it produces is highly thermoformable and puncture-resistant, Kerfoot said, with excellent gauge uniformity and interlayer thickness uniformity.
“We’ve installed 17 AquaFrost systems worldwide,” he remarked. With an eye toward continuous quality improvement, Kerfoot said Brampton has fine-tuned the system to achieve faster purging times and to improve changeover speed. “Changeovers can now be done in 15 minutes,” he said.
Hunger for transparency
Scott Ludwig, business development manager - Americas for Kortec, presented a solution aimed at making canned foods more appealing to consumers. An alternative to metal cans for fruits, vegetables, soups, meats, etc., the multi-layer KlearCan has a transparent body and bottom. It can be used with either standard or easy-open metal can ends.
Ludwig explained that to make the KlearCan, Kortec uses co-injection molding technology to pair polypropylene (PP) with an ethylene vinyl alcohol (EVOH) barrier layer for extended shelf life. KlearCans are fully retortable up to 130ºC, BPA free, dent-resistant and stackable, and have a two to five year shelf life, he said.
Ludwig told FoodProductionDaily open-ended KlearCans are delivered to the filling facility palletized, just like traditional metal cans. “We have designed the can so that all of [a brand owner’s] downstream equipment is used in the traditional method,” he said.
“The only potential difference is that in some facilities the metal cans run on magnetized conveyors, which of course wouldn’t work with plastic. In these cases, an alternative conveying method may be required.”
The KlearCan system is available in three sizes: a 4-cavity, 280mt machine that can produce 12.5m cans per year; an 8-cavity, 280mt machine with an estimated annual output of 25m cans; and a 32-cavity, 650mt machine that can produce approximately 85m cans per year.
Going to market
The KlearCan system debuted at Interpack in May. Ludwig said Kortec currently has several development projects in the works with food companies in North America and around the globe. “My guess is that you will see some fruit products on the shelf in America by late 2015,” he said.
The KlearCan plays into a growing trend in food packaging, i.e., letting consumers see the product before they buy it.
“Brand owners tell us that their focus group feedback is the consumer likes to see the food — it gives them a sense of freshness,” Ludwig said. “This is why we are mainly targeting fruits and vegetables, food that looks good.”
