The Packaging Machinery Manufacturers Institute (www.pmmi.org) observed its 50th-anniversary Pack Expo in November 2006 in Chicago with a mammoth exposition plus a conference program with celebrity keynoters and all sorts of doings.
Having participated in well over half of the events as program chair, speaker, and visitor/floor walker, I commend PMMI for another milestone. Like so many others, I have exhausted shoes, legs, ankles, knees, back, and brain walking the myriad of aisles to gain insights into the very latest in packaging that could benefit the food packaging community now and in the future.
PMMI has also undertaken the daunting and wonderful task of identifying and celebrating the professionals among us who have percolated up to leadership positions in packaging technology, engineering, and business. PMMI’s Packaging Hall of Fame inducted two giants from food packaging, Bruce Harte, professor and former director of Michigan State University’s School of Packaging, and Ed Bauer, former director of packaging technology at Campbell Soup Co. That half of the 2006 inductees came from the food packaging universe is a reflection of the significance of this discipline to the entire world.
But what of the event itself? What among the more than 1,900 exhibitors and dozens of speakers might be highlighted for food scientists, technologists, and packaging folks? Somehow, I feel like a print media movie or book reviewer at the year end: having seen hundreds of films or read hundreds of publications, some great and some not-so-great, I am compelled to select ten or so best based on my experience and judgment. My perspective, of course, is those innovations that might have the greatest influence on food packaging in the coming years. Radiofrequency identification (RFID), nanotechnology, and sustainability are the hot packaging topics at the moment and have been discussed in detail in my previous Packaging columns. One intriguing observation: very few exhibitors offered products or services related to sustainability or nanocomposites.
Nevertheless, some fascinating packaging innovations surfaced worthy of inclusion in my list of "bests."
• Time–Temperature Integrators (TTIs). Invented at Israel’s Technion and developed at the University of Bonn, Germany, OnVu™ from Freshpoint (www.onvu.com) differs from other TTIs in that it can be printed on package surfaces and activated by ultraviolet radiation immediately prior to use. Ciba Specialty Chemicals, which is helping to market the concept, supplies temperature-sensitive ink presently applied to pressure-sensitive labels placed on the package surfaces. The mechanism of the TTI was not disclosed, although it was referred to as "organic crystals." Prior to use, the labels may be stored at ambient temperatures. Currently, a Bizerba labeler is employed to apply 20–30 labels/min and activate (called "charging") them using LED UV radiation and to apply a UV-blocking film to obviate the effects of incident UV radiation that otherwise would interfere with temperature/time indication.
The TTI may be calibrated to any temperature range desired. The indication of change is fading of the color compared to an associated printed reference color. Data offered suggest that the color fading follows the Arrhenius model very well.
Cost of the label is about 5 cents, and cost of the on-package printed versions, including the UV inhibitor, is projected to be about 1 cent.
A device called a Time Strip from Israel by way of Hichins in the United Kingdom (www.Smurfit-stone.com) is really another TTI. The mechanism is oil diffusion initiated by breaking a bubble of oil to diffuse visibly along a porous path. Cost is 16–20 cents.
• Aroma Emitters. Sud Chemie (www.s-cpp.com) offers Aroma-Can™ injection-molded plastic canisters modeled after desiccant canisters to contain encapsulated Aroma Release™ technology from Scentsational Technologies LLC. The canister contains food-grade flavors such as lemon that are continuously evaporated into the internal package environment through the openings in the canister end.
• Flexible Plastic Water Bottle. Ampac (www.ampaconline.com) has developed a standup flexible pouch for water fabricated from polyester/polyethylene film. Closure for the PureFlex™ pouch is a Seaquist Smart Spout™ with an internal silicone device that automatically opens with internal pressure and closes when the water pressure is relieved. Although not the first water package fabricated from flexible materials, Ampac’s offering might spur some bold water bottler to try this as one distinctive alternative to the ubiquitous PET bottle. And, of course, this particular version of a standup flexible pouch might spark some interest among other beverage packagers to reach further.
• Plastic Canisters. Dry and semi-moist foods are packaged in a variety of package structures, ranging from metal cans to polyester jars to paperboard canisters, flexible pillows, and standup pouches.
Entering the competition are a number of different plastic canisters, some of which are preformed, such as injection-molded polypropylene from Berry Plastics (www.berryplastics.com) for raisins for offshore shipment. Raisins for domestic distribution are generally packaged in either recycled paperboard cartons or convolute-wound paperboard canisters, neither of which offers sufficient moisture barrier for prolonged storage, Polypropylene’s water vapor barrier offers enough moisture barrier for overseas shipment. Canisters are decorated with full-body shrink-film labels.
Paper Machinery Corp. (www.papermc.com) and Huhtamaki (www.huhtamaki.com) have adopted their in-line convolute-wound paperboard-canister manufacturing equipment for in-line fabrication of polypropylene sheet to deliver polypropylene canisters analogous to the Berry Plastic injection-molded version.
• Case-Ready Meat Packaging. A case-ready fresh red meat system from Cryovac (www.cryovac.com) is Triweb, a three-film tray package currently in use in Europe. The preformed or in-line-formed plastic tray is fabricated from a barrier plastic such as ethylene vinyl alcohol (EVOH)/expanded polystyrene. The meat is placed in the bottom, and a vacuum skin pack (VSP) is applied to drape the film over the meat contour. The inner film may be barrier or nonbarrier. A second flat film is sealed to the tray flange to form a gas-tight seal. Between may be a gas flush.
The purpose of the structure is to retain the meat in place when in vertical or near-vertical posture in display. The package may function in an enhanced fashion by using a nonbarrier interior film to allow air to enter and rebloom the meat when the outer film is removed.
Case-ready meat packaging is not new, but the application to ground beef by Reiser (www.reiser.com) is intriguing. Ground beef is placed in a thermoformed barrier soft plastic tray that is evacuated and closed with a flexible barrier film (think hot dog packaging). The ground beef, visible because it is displayed open face up, is low-oxygen purple myoglobin color in the tight package.
Currently applied in Europe and also by Wegman’s retail chain in upstate New York, the off-color meat package appears to be gaining consumer market acceptance. Does any success with this package signal that a large consumer segment is less than obsessively concerned with red meat color than previous conventional wisdom has suggested?
• Liquid Nitrogen Purging. Formerly VBR, Cryotech (www.cryotechinternational.com) offers some new technologies to introduce liquid nitrogen into aluminum cans, polyester bottles, and dry-product composite paperboard canisters. Liquid nitrogen functions to counter pressure to maintain the structure of beverage packages filled hot, which normally produces vacuum due to condensation of steam when the temperature is reduced to ambient. An added benefit is to counter pressure to permit thinner walls—as in reducing the mass of polyester in a bottle structure, e.g., to eliminate the petaloid base. Liquid nitrogen also purges most (but not all) of the oxygen from the headspace to help extend shelf life.
Cryotech’s Soft Dose™ employs a ventilator spray dispenser to disperse discrete particles of liquid nitrogen over the surface of the product, a gentler means than diverging or continuous streams for introducing the gas into the headspace. The system disperses the liquid nitrogen so broadly that it can be applied to the interiors of dry powder products such as milk powder.
Among the products now employing Cryotech liquid nitrogen injection are vinegar; Karo syrup (warm filled in PET bottles); and Martinelli apple juice hot filled in an apple-shaped PET bottle that resembles its classic glass apple.
• Retort Pouch. Cryovac has introduced a remarkable retort pouch for foodservice applications, the Flavour Mark™. Using a base of Orihiro Onpac vertical form/fill/seal technology, the company’s Onpac 2070 machine has been modified to produce No. 10 can replacement pouches 6.5–12 in wide and 7–18 in long. Approximate content weight is 3.1 kg or 6+ lb. Output of the current equipment is 20–25 pouches/min. The Japanese-built machine is capable of dual fill, i.e., filling two different food components simultaneously.
The recommended package material is a multilayer barrier structure incorporating a blend of nylons as the principal gas barrier plus polyolefins for the water vapor barrier and heat sealant. Back-side heat seal is overlap, using the Onpac roller just prior to sealing to reduce seal contamination. Cross seals are multiribbed to reduce the probability of seal failure.
Retorts for sealed pouches are preferably water spray, such as LaGarde, Steriflow, and others, but steam/air and water have been used effectively. First customer of five active in North America is La Costena in Tulpetlac, Mexico, for a number of bean products. Typical prices for No. 10 can–size pouches are 35 cents each.
A developmental, second-generation, higher-speed, continuous-motion machine, the Onpac 2075, was exhibited with added features such as inert gas filling.
• Form/Fill/Seal Machines. Germany’s Rovema (www.rovema.com) has developed and is marketing in conjunction with converter Printpack (www.printpack.com) the Viscopack™ vertical form/fill/seal machine intended to compete with Cryovac’s Onpac. This machine is a servo-driven continuous-motion machine that produces three-side-sealed pouches of about 1.5-L capacity at 60 packages/min. They claim that the machines have a range of 6 oz to 2 gal, largely targeting foodservice applications, as does the Onpac system. These liquid fillers use a roller (squeegee) to remove product from the transverse seal area to minimize seal contamination.
Printpack is the primary marketer offering roll stock materials with blown coextruded nylon or nylon/EVOH core for gas barrier. The marketing program involves leasing. Estimated cost of each 1.5-L pouch is less than 20 cents.
• Another vertical form/fill/seal machine, this one from Rexroth/Bosch (www.rexrothbosch.com), is an all-servo-driven machine in continuous-motion mode that can achieve up to 200 pouches/min if the product is capable of gravity dropping that rapidly. The unique feature of the machine, however, is the absence of any heating bands, which are a constant replacement part for vertical form/fill/seal machines. In their place is a forced-hot-air sealer in close proximity with both sealing surfaces. Heating is at 120°C, much lower than conventional contact heaters and therefore less damaging to the material. The hot air also cushions the film to reduce damage in the heat-seal area.
• Aseptic Equipment. In a report commissioned by Serac (www.serac-usa.com), French manufacturer of aseptic/extended-shelf-life (ESL) equipment, polyester (PET) bottles were perceived to have the best consumer acceptance over paperboard cartons, bag-in-box, and high-density-polyethylene bottles. Aseptic was preferred by packagers over ESL because of the logistics savings and the ability to cover a larger geographic area. The main barrier to PET bottles for aseptic packaging is the Food and Drug Administration’s concern about sterilants. Serac believes that peracetic acid, long used in Europe for sterilization of low-acid foods, will shortly be accepted by FDA, thus opening the market significantly. Copies of the report may be obtained from the company.
In an aseptic blow-mold/fill/seal machine from Weiler Engineering (www.weilerengineering.com), the thermoplastic is extrusion blow molded in a closed environment with sterile air while sterile liquid product is filled into the bottle as it is fabricated. Thus, the sterile liquid enters a sterile package which is immediately sealed in the mold. Blow-mold/fill/seal systems are routinely used for packaging ophthalmic fluids and only occasionally for foods such as fruit and dairy beverages. Asep-Tech® blow/fill/seal systems are capable of bottle sizes up to 1,500 mL at outputs of up to 2,400 packages/hr. One issue that is still not resolved is that the main package material is high-density polyethylene (HDPE), which is not a good oxygen barrier.
Inclusion in this "best of show" list does not automatically mean that these are unanimous bests of the best. Some people might disagree with my rankings, but none can claim that those selected here cannot enhance some food companies in their future packaging, as several have already begun to do.
by Aaron L. Brody, Ph.D.,
Contributing Editor, President and CEO, Packaging/Brody, Inc., Duluth, Ga.