In food and beverage packaging, function often takes a back seat to form. Take a recent sales promotion at Safeway Inc.'s Dominick's supermarkets in metropolitan Chicago: on one page, the flyer featured a gallon of milk in an unglamorous high-density, polyethylene plastic jug for $2.50, available in chocolate and all fat levels of white. On the next page, a single-serve PET container with one-eighth as much product was promoted for $1. For three days, not seven. In white, only.

Laser scoring is performed on roll stock at CLP Industries' production facility. The printer/converter is applying the technology to create microperforations for breathable film. Source: CLP Industries Ltd.

If sizzle outsells steak, why invest in high-performance containers when eye-catching graphics or a funky new shape moves product?

Beauty can and should be more than skin deep, and packaging suppliers are investing the capital needed to develop the next generation of materials. The thermoplastics segment is most vocal about functional improvements in development or those coming on line, though other material suppliers are singing from the same hymnal. Glass, metal, even paper converters are eager to shed their low tech, commodity images by introducing innovations.

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DuPont is taking the lead in reframing the discussion by focusing on packaging's role in delivering freshness, not just convenience. The polymer provider commissioned consumer research last year to highlight the problem of food spoilage and the link with underperforming packaging. DuPont's initiative targets barrier films for perishables, one of the fastest growing applications for plastic films. Research by Kline & Company Inc. pegs annual growth in this segment at 5.4 percent.

DuPont's study, based on 1,172 on-line consumer surveys conducted by Ipsos Public Affairs, found that one-third of respondents recalled throwing out in the previous two weeks food they purchased that was not fresh. Fresh vegetables and pre-cut salads accounted for the most frequently discarded products (58%), followed by fresh fruits (49%). Packaging for those types of products accounts for approximately 5 percent of the retail price, points out Donna L. Visioli, senior technical program manager at DuPont Packaging and Industrial Polymers, Wilmington, DE. The survey also found that 58 percent of consumers would be willing to pay an additional 3 to 8 percent for packaging that ensures freshness. The implication is that food companies are unnecessarily shortchanging their customers with inferior films. Higher price points while fostering better brand loyalty, suggests Visioli, can recoup spending on high-performance films for convenience foods like ready-to-eat produce.

A sea of beer bottles moves down a line at O-I's new Windsor, CO, facility, the first new glass bottling plant in a quarter century. Source: O-I.

The promise of freshness

Unlike cans, modified atmosphere packaging (MAP) for produce is not supported by on-line inspection tools that can spot pinholes and other package imperfections. "If you have an imperfection in the seal area, it will grow," Visioli says, and the likelihood of spotting the problem before the product leaves the plant is remote. Chemical engineers are focusing on improving the performance of sealant resins such as DuPont's Appeel and Dow's Affinity lines.

"There has been a huge shift toward deli meats and cheeses packaged in MAP," according to Jeff Wooster, senior value chain manager at Dow Chemical in Freeport, TX, and it's been made possible by polyolefin plastomers that can maintain seal integrity despite the presence of food contaminants on the surfaces being joined. The shift was on hold until new generation sealant materials and barrier polymers began to be commercialized. "The right material just wasn't available before," he says.

Ready-to-eat and fresh meats drove improvements in high-integrity sealants in recent years. The new frontier is fresh-cut fruits and vegetables, though film suppliers have to demonstrate that MAP technology has matured and can deliver on the freshness promise. A chemical engineer with numerous patents involving flexible packaging for fresh-cut produce to his name, Wooster believes the business case for superior films has yet to be made to processors. Higher costs are more than offset by fewer product returns and less out-of-code food, he maintains.

"There's a ho-hum attitude among a lot of the producers," says Wooster. "They're hesitant to make a big investment in new technology until they're shown how it can reduce their supply chain costs or return costs."

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"Tailored permeability is a need that has not been completely met," DuPont's Visioli concedes. Meat is a simple product: if more barrier protection is needed, a thicker film will suffice. With fruits and vegetables, "more barrier isn't necessarily better," she notes. Some oxygen is needed; at the same time, carbon dioxide must escape or the product will quickly deteriorate. Cut fruit requires a very breathable structure. "A package of pineapple will literally blow up if too much carbon dioxide builds up," says Visioli. Breathable films are a particularly active development area.

Microperforations are one way to control respiration. Mechanical systems are being developed, but "100 or 200 micron holes can only be done with laser scoring," insists Rani Stern, chief technology officer at Sdi Gat, Israel-based CLP Industries Ltd. The converter and printer of flexible packaging has used lasers to create easy-open pouches for several years ("Score one for laser perforations," Food Engineering, April 2003).

"The laser scoring system to control the diameter and intensity of the holes is still under development, and the number of holes must be adjusted for each kind of vegetable to match its breathing rate," says Stern. Nonetheless, early results are encouraging. A southern Israel producer of sliced carrots recently switched from a polybag to laser perforations. "It's a tremendous success," he reports. "They're getting almost 40 percent longer shelf life."

Sealed Air Corp.'s Cryovac division rejected laser perforation in favor of permeable film in adapting its Simple Steps packaging for produce. Smithfield Foods used the system for heat-and-serve meats in fall 2002 ("Packaging as convenient as the product," Food Engineering, March 2003). Now, California produce companies are testing using Simple Steps with refrigerated broccoli, zucchini and other vegetables.

Simple Steps uses a polypropylene tray with a large seal area to create a self-venting cooking system for microwave use. While the film covering the tray for meat products is high barrier, the vegetable application is "highly permeable to allow enough oxygen into the package and let the carbon dioxide out," explains Myra Foster, new business development manager at Duncan, SC-based Cryovac. Consumers do not pierce the film before microwaving. Instead, the sealed container is heated for two to three minutes, with the water within the vegetables generating steam to cook the product. "It's a more healthy way to prepare vegetables than boiling," maintains Foster.

Breathable films had to be developed to adapt Cryovac's Simple Steps self-venting microwave packaging for produce. Source: Cryovac.

Best defense is offense

Consultant Mary Ellen "Mel" Reis scoffs at health claims related to cooking with plastics, citing the controversy swirling around bisphenol A polycarbonate. Her skepticism may be colored by her role as a spokesperson for the Glass Packaging Institute (GPI). But sniping at plastics won't stanch the migration to lightweight plastics for food and beverage packaging: makers of traditional materials also must improve functionality.

Can manufacturers have tried to fabricate microwavable metal containers, though the hurdles may be insurmountable. "It's technically feasible, but the container has to have such a low aspect ratio that it's not commercially viable," reports Daniel Abramowicz, executive vice president of technology and regulatory affairs at Crown Holdings Inc., Philadelphia. Undeterred, can makers are pushing the innovation envelope to address shortcomings and shed a stodgy image. Says Abramowicz: "Metal has a dated image, and some of the changes we're making are designed to address that."

Hourglass-shaped cans produced for UK-based Premier Foods' Waistline diet foods take advantage of a new blow-forming process developed by Crown. By expanding the top and bottom of the can instead of the middle, Crown was able to produce a container that conforms to conventional retorts and works with high-speed fillers, says Abramowicz. Similarly, Crown's engineers have designed seamer tooling that "essentially eliminates changeover" between sanitary ends and Crown's easy-open, low-energy pull-tabs for self-opening cans, he says. Changeovers were taking 20 to 30 minutes.

A number of other technical advances are in development, including reclosable beverage cans, self-heating cans, polymer coatings that extend metal's ability to stretch and specialty inks for digital printing on metal sheets, speeding product rollouts and accommodating shorter production runs.

"Customers will always put pressure on taking cost out," Abramowicz adds, "but we have sensed a change over the last couple of years. Food and beverage companies are placing new emphasis on differentiating product on the shelf."

Shelf appeal and more efficient shipping and handling are possible with rectangular packaging, but seaming a rectangular can takes longer than seaming a round one. Lower weight material can counterbalance the filling problem, and paper is one of the lightest materials around. Tetra Pak spent more than a decade overcoming the technical challenges of a retortable paperboard container to deliver Recart, a rectangular container that stacks easily and packs visual punch on supermarket shelves.

Hormel Foods installed North America's first Recart line for its Stagg and Hormel chili lines in 2003. The change lifted flat sales in a moribund category: Stagg and Stagg Classic unit sales bounced up 12 percent from fourth quarter 2003 to fourth quarter 2004, according to Information Resources Inc., though unit sales slipped in 2005's comparable period by 2.8 percent. Organic foods marketers are interested in using Hormel's excess capacity. The ability to attain sterility with less thermal transfer and produce a shelf-stable product without preservatives is particularly attractive to the fast-growing natural and organic foods market.

For products with price points that support premium packaging, the light refractance of glass is a benefit that's hard to match. Source: Glass Packaging Institute.

Organics marketers also are opting for glass containers. Ocean Spray's research indicated likely buyers of its Organic 100% Juice Blends favor glass for its pure and clean image. Likewise, Safeway opted for glass bottles and jars for O Organics, a private label line of more than 150 certified-organic products.

Despite strong growth in the last decade, organics are still a blip in overall food and beverage sales. To gain new users, glass suppliers need to address mainstream needs, particularly safety. "The two-decade focus on cost reductions has distracted the glass industry from innovation," acknowledges Michael Lonsway, new product development director at Toledo-based O-I (formerly Owens Illinois Inc.). "Just as we invested in resources regarding weight issues with glass, we have also begun working on the development of shatter-resistant glass packages."

The first new North American glass plant in a quarter century came on line last year when O-I opened its Windsor, CO, facility, which fabricates 1,200 bottles a minute for a nearby Anheuser-Busch brewery. Beer represents 52 percent of the glass packaging market, according to GPI's Reis, and the material's imperviousness to oxygen, quality image and recyclability will forestall more inroads by plastic. "Tinted plastic is a major recycling issue, and with the price of oil increasing, they can't make plastic beer bottles as cheaply as glass," she says.

Greater strength and lighter weight remain the primary focus, however. By the time Reis left her position as vice president-packaging at Snapple, the beverage firm's bottles weighed half as much as they had 20 years earlier. The material's load-bearing properties also are an advantage over plastic when it comes to building P-O-P displays or stacking pallets, she says.

But glass makers have limited opportunities to add function. Perhaps the material's quality image is enough. GPI honored Rose's Cocktail Infusion with its Clear Choice Award based on visual appeal. "Rose's could have put the mix in a plastic bottle with the same curves," says Reis, "but the bottles wouldn't have stacked as well, and they wouldn't add as much visual sparkle on a bar."

Aesthetics aside, people want packaging that offers both safety and protection for the foods they consume. Certainly, appearance is important: until developers of aseptic plastic pouches taught their creation to stand up on a retail shelf, the material's light weight and low cost were not enough to gain converts. The consensus among material providers is that the age of conversion is over. Opportunity resides in new foods and beverages, and the materials that deliver the best performance will become the standard for those products.

For more information:

Rani Stern, CLP Industries Ltd., 001-972 8 679 0320,

Daniel Abramowicz, Crown Holdings Inc., 215-698-5143,

Jeff Wooster, Dow Chemical Co., 979-238-2011

Scott Nelson, DuPont, 302-992-6678,

Mel Reis, Packnology, 802-592-3208,

Jeff Kellar, Tetra Pak Inc., 847-955-6680,