Anne Marie Mohan

January 29, 2014

13 Min Read
Farmers lend an ear

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For Italian supermarket chain Iper, a back-to-basics approach to fresh food products will soon include the use of a natural packaging alternative that literally has its roots in America's heartland. By mid-summer, '02, all of Iper's 21 locations will be dishing out fresh fruits, vegetables, pasta and salad in fully compostable thermoformed containers with clear film lidding that are created entirely from resins derived from Midwestern-grown corn.

Pioneered by Minnetonka, MN-based Cargill Dow, LLC, NatureWorks™ PLA resin is produced when carbon is harvested from 100-percent renewable resources. With the opening of its first large-scale production facility in Blair, NB, last April (see sidebar), Cargill Dow estimates that approximately 16 million bushels of locally grown corn will be consumed each year in the manufacture of this polylactide (PLA) polymer.

The breakthrough technology used to produce NatureWorks PLA is said by Cargill Dow to use 20- to 50-percent less fossil resources than is required to make petroleum-based resins and releases less carbon dioxide emissions.

Iper, one of the

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A marketing coup, Italian supermarket chain Iper is instituting 'natural-in-natural' products and packaging in all 21 of its locations, offering fresh fruits, vegetables, pasta and salad in containers made from PLA resin, derived from corn.

first adapters of NatureWorks PLA, sees the opportunity to provide a complete "natural-in-natural" product to its customers as a significant competitive advantage. "Our goal is to offer quality products to consumers without causing a negative impact on the environment," explains Mario Spezia, Iper sales director. "NatureWorks PLA is a versatile material that allows us to provide our customers with a natural food product protected by a natural package–an important combination that allows us to differentiate ourselves from the competition."

A new alternative
Established in 1974 when the current proprietor severed his ties with European-based retailer Carrefour, Iper boomed in the late '90s and is now the fourth-largest supermarket chain in Italy. Of its 21 stores, 18 are located in Northern Italy, while three serve Central Italy.

In '99, after having cultivated a reputation for providing high-quality fresh foods and offering competitive prices, Iper began to look into ways of expanding its product benefits to customers by using more environmentally focused packaging. The challenge, says Spezia, was balancing ecological concerns with packaging performance. "While we wanted to develop a packaging concept that served the best interests of the environment, we did not want to sacrifice the quality of the end product," he says.

In search of an alternative packaging material for its fresh food selections, Iper representatives attended the Interpack '99 trade show in Germany. The ideal material would not only have to provide sufficient rigidity and strength, recalls Spezia, but it also had to be "transparent to showcase the food product contained within, beneficial for the environment, and easy to use in the store." Visiting with Cargill Dow, Iper found the solution.

"The versatility of NatureWorks PLA as a packaging material, combined with the environmental benefits associated with the polymer, appealed to us," says Spezia. "NatureWorks allowed us to create a high-performance package with the environmental qualities we wanted."

According to Cargill Dow, packaging made from NatureWorks PLA offers a number of characteristics equal to, or better than, traditional, petroleum-based polymer packaging. These include high clarity and gloss, with 2.1-percent haze; unique flavor and aroma barrier properties; excellent resistance to most oils and fats used in food products; and low-temperature heat-sealing requirements of 176 deg F, with heat-sealing strengths of greater than 2 lb/in. Extremely versatile, the material can be used to make films, rigid containers and bottles, and can be oriented, thermoformed, coated and printed with existing converting equipment at high speeds, reports Cargill Dow.

PLA pioneers, partners
In preparation for a test run of NatureWorks PLA-based packaging in five of its supermarket locations in fall, '01, Iper worked with European packaging suppliers Autobar and Trespaphan GmbH to develop thermoformed containers and film lidstock, respectively.

The Autobar Disposables Group, a pan-European manufacturer of disposable foodservice products trading under the name Veriplast Intl., began its experimentation with NatureWorks PLA in '97. Recounts Anne Sutton, product development manager for Autobar, "Work by the group with NatureWorks PLA began in mainland Europe, when we manufactured yogurt containers for a large European dairy to be used for trials in the German market over 1997 and 1998. While the containers were found to be successful, the systems to segregate the compostable materials were not yet developed.

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Ensuring product freshness, each Iper location is equipped with heat-sealing equipment that allows store employees to fill and seal packages as needed, left. Many products are packaged in large quantities and displayed within the supermarket, right. Others can be selected by customers to be packaged at point-of-sale.

"Subsequent trials took place in other packaging markets, and these showed considerable promise," she adds. After significant input on the thermoforming of NatureWorks PLA, Autobar was recognized by Cargill Dow as one of its development partners.

Autobar's initial work with Iper consisted of developing off-line samples for Iper's approval created from the thermoform molds previously used to produce the retailer's OPP containers. The packaging consists of 12 sizes–categorized as "small," "medium," "large" and "maxi"–that offer a range of dimensions. For example, the small container measures 5.6 x 3.6 in. and is available in depths of 1.2, 1.8 or 2.4 in. After approval of the containers by Iper, Autobar began commercial production of the test-market packaging.

At its plant in Mont-de-Marsan, France, Autobar begins the production process by creating 330-micron film sheets from the NatureWorks PLA resin using a standard cast extrusion line. Says Iper's Spezia, "By using NatureWorks PLA instead of polypropylene, we are able to reduce the thickness of the containers, from 460 microns down to 330 microns. Down-gauging allows us to use less material, which helps reduce the production costs, but it doesn't compromise the quality of the thermoformed container."

The extruded sheet is then thermoformed using equipment from a supplier that that Autobar prefers not to identify.

To supply the film lidding for heat-sealing onto the container, Iper went to Trespaphan GmbH, a multinational producer of oriented film products based in Raunheim, Germany. Trespaphan, which markets the PLA film product under the tradename Biophan®, is also a Cargill Dow partner.

Using a standard process for producing biaxially oriented polypropylene, Trespaphan manufactures the clear film overlay to a thickness of 20 to 25 microns, and supplies it to Iper as rollstock.

Change proves fruitful
Last fall, Iper began using packaging made from NatureWorks PLA in five of its locations. Says Spezia, "The response from consumers has been very positive, which is why we decided to expand the use of the packaging to all twenty-one of our stores."

Ensuring maximum freshness of the fruits, vegetables, pasta and salad distributed in the new packaging, each Iper location is equipped with heat-sealing equipment that allows store employees to fill and seal the packages on an as-needed basis. While many products are packaged in large quantities and displayed within the supermarket, others can be selected by customers to be packaged at point-of-sale.

To generate enthusiasm for its natural-in-natural products and packaging, Iper has launched an in-store advertising campaign that includes signage that educates customers about NatureWorks PLA. In addition, all employees undergo a training session developed by store management that teaches them about the material so that they will be able to fully answer customers' questions about the new packaging. "Using NatureWorks sets us apart from our competition by offering a package no other supermarket has," Spezia explains. "This point-of-sale differentiation allows us to make a common product unique by packaging it in a nature-based container." And, in terms of its performance, NatureWorks has fully satisfied Iper's requirements, he adds. "As far as performance, we have seen no difference between our packaging made with NatureWorks PLA and petroleum-based packaging," he says. "NatureWorks PLA provides the strength, stiffness and clarity needed to produce a quality thermoformed container."

But, that quality does not come without a cost. According to Spezia, the price of NatureWorks PLA is approximately twice that of PP. "However, due to our commitment to the environment and our customers, cost is not a concern," he says, "as long as we receive a quality product that fits our goals as a company." Just the beginning
With the rollout of NatureWorks PLA-based packaging in all 21 of its locations, Iper estimates that its yearly consumption of the material will reach nearly 500 tons. But that may be just the beginning for this environmentally responsible retailer. "NatureWorks PLA delivered the performance we were searching for, so much so that we are beginning to explore the use of the material for packaging our private-label products in all of our stores," Spezia relates. "On average, our line of private-label products accounts for four percent of our total annual sales. Judging by the response we've already seen by customers, using NatureWorks in this area will prove positive for Iper."

Cargill Dow's converting partner, Autobar, also sees a bright future for the use of the sustainable packaging. Says Sutton, "We believe that the future for PLA is exceptional, especially when the price of the raw material reduces as demand grows and economies of scale begin to take effect, reducing the costs of production.

"As consumers become increasingly committed to the need to take a responsible attitude toward protecting their environment, the demand for compostable/biodegradable materials will increase," she adds. "Retailers will use PLA to differentiate themselves from competitors and to provide an opportunity for philosophical communication with their customers."

More information is available:

PLA resin: Cargill Dow, LLC, 877/423-7659; www.cargilldow.com. Circle No. 224.

Thermoforms: Autobar Disposables Group, +44 (0)20 8326 8000. Circle No. 225.

Film lidstock: Trespaphan GmbH, +49-(0)6142-200-0. Circle No. 226.



A 'second industrial revolution'

On April 2, '02, Cargill Dow, LLC president and CEO Randy Howard heralded in what he referred to as a "second industrial revolution." In a grand-opening ceremony, the company unveiled its new facility in Blair, NB–the world's first global-scale manufacturing plant capable of making commercial-grade plastic from annually renewable resources.
Said Dr. Patrick Gruber, Cargill Dow's vp and chief technology officer, during the ceremony, "Now we're in the game for real, and we can go out and change the world."

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Renewable resource
Unrefined dextrose

A renewable resource such as corn is milled, separating starch from the raw material. Unrefined dextrose, in turn, is processed from the starch. Future technology enhancements may eliminate the milling step and allow for utilization of even more abundant agricultural byproducts.

Fermentation
Lactic acid

Cargill Dow turns dextrose into lactic acid using a fermentation process similar to that used by beer and wine producers. This is the same lactic acid that's used as a food additive and is found in muscle tissue in the human body.

Intermediate
production
Lactide

Through a special condensation process, a cyclic intermediate dimer, referred to as a lactide, is formed.

Polymer production
Polylactides

This monomer lactide is purified through vacuum distillation. Ring-opening polymerization of the lactide is accomplished with a solvent-free melt process.

Polymer modification

A wide range of products that vary in molecular weight and crystallinity can be produced, allowing Cargill Dow to modify PLA for a large number of applications.

For Dr. Gruber, the plant opening was a dream realized. For more than 10 years, he led Cargill's Renewable Bioplastics project, now known as Cargill Dow's NatureWorkse PLA, which relies on ordinary field corn to produce polylactide (PLA) polymers that can be used for a range of packaging and textile applications. Packaging applications introduced thus far include soft drink cups for The Coca-Cola Co., used at the 2002 Olympic Winter Games in Salt Lake City, golf ball packaging for Dunlop Pacific, and film wrap for Sony Pacific's mini-discs, among others. And, Cargill Dow representatives indicate that commercial launches of PLA bottles can be expected later this year.
The new facility in Blair encompasses more than 16 acres of Missouri River bottomland and stands on a site that was once, itself, a cornfield. The plant is capable of producing more than 300 million pounds of NatureWorks PLA per year–50 percent of which will be used for packaging applications, and 50 percent for textiles–and uses up to 4,000 bushels of locally grown corn per day as the raw material for the manufacturing process.

To create the resin, the facility "harvests" the carbon naturally stored in simple plant sugars when a plant–in this case, corn–undergoes photosynthesis. Through simple fermentation and distillation, Cargill Dow extracts the carbon and uses it as the basic building block for commercial-grade plastics and fibers. In contrast with traditional thermoplastics that rely on petroleum as a base feedstock, the company is using raw materials that are annually grown and in abundant supply.

"The idea of creating a more sustainable business model is to establish a new industrial system where society can go on forever without depleting the earth's natural resources, without compromising people and helping to create a better quality of life," says Dr. Gruber.

From the corn planter to the retail counter, NatureWorks PLA has a life cycle that reduces fossil fuel consumption by up to 50 percent, Cargill Dow reports. In addition, they say, the process to make the polymer generates 15- to 60-percent less greenhouse gasses (GHGs) than the material it replaces. Research also shows that technology advancements in PLA could allow up to an 80- to 100-percent reduction in GHGs, notes the company.

For the past several years, Cargill Dow has test-marketed its PLA resins in arenas including Europe, Asia Pacific and North America. Until the opening of the Blair plant last November, however, the company was limited in its ability to satisfy increasing demand, producing PLA from a semi-works facility outside of Minneapolis capable of just 17 million lb/yr.

Says Jim Hobbs, Cargill Dow's commercial director for packaging, "The grand opening signaled an exponential increase in the amount of product we can deliver to the market. It was also a clear sign to the packaging industry that we are a serious player and have the capacity to be more than just an innovator, but a true global leader."

Despite the massive increase in availability of the material made possible by the new plant, Lisa Owen, commercial leader, Rigid Packaging, for Cargill Dow, says "there is less excess capacity than you would imagine."

"We don't expect to see a lull in production," she adds. "Our partners have already begun ramping up."

Offering a staggering statistic, during a special media plant tour of the new facility, Cargill Dow related that approximately 1.4 billion barrels of oil will be conserved this year because of the PLA plant. This not only bodes well for the environment, but, with an approximate 2.2 lb of corn needed for each 1 lb of plastic, it also represents significant growth opportunities for local farmers.

Cargill Dow is now in Phase II of the plant's development, adding a lactic acid plant that, when finished, will supply 400 million lb of lactic acid/year, or two-thirds of the world's supply. Future investments, says the company, will in part focus on the development of technology to enable the conversion of biomass (such as corn stalks, wheat straw, grasses and other agricultural waste products) into PLA.

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