Aaron L. Brody

Flip through packaging trade and technical journals, and you will see two technologies vying for space: polyester beer bottles and case-ready fresh red meat. Prowl the pages of beverage magazines, and you will see that the dominant discussion is about plastic beer bottles. Look no further than the covers of meat trade publications, and the sole topic seems to be “case ready is here,” or “case ready credentials,” or some such headline.

And accessing the Web on food packaging drags the reader to the two technology families, unrelated except for their impact on their respective product contents—and for the monumental technical achievements each represents. Each has been studied and discussed for more than 40 years for its potential to totally alter its part of the food industry. Plastic bottles would replace traditional glass bottles and aluminum cans for beer, and significantly extend distribution by providing consumers with the added value of take-it-anywhere convenience, a repeat of the dramatic exponential growth of carbonated beverages during the 1970s through 2000. Centralized packaging of fresh red meat—making the product “case ready”—would displace supermarket-back-room cutting and packaging, and deliver not just an ingredient for cooking but a prepared product ready-to-heat-and-eat, just as poultry shot past all other protein foods in the 1980s riding on the wings of some intricate technologies and distribution enhancements.

A race is on in packaging circles to determine which of these two will win the brass ring of packaging eminence in the 2000s. I hesitate to predict a winner and elect rather to devote this column to offering data to enable readers to decide for themselves between these two technologies that are of interest to many and of concern to plastics converters and machine makers.

The late 2001 publication of mammoth multi-client reports on case-ready fresh meat and polyester beer bottles by Packaging Strategies, West Chester, Pa., reflects the dual thrusts occurring in the food packaging community. My nearly year-long involvement on the case-ready fresh red meat study with the assistance Anne Bieler of IFT’s Food Packaging Division suggests the magnitude of the task of trying to sort out the multiplicity of technologies, commercial entries and departures, challenges, and opportunities.

Poultry long ago converted from its archaic delivery of whole birds in ice in wire-bound crates to cut-up parts in film-wrapped expanded polystyrene (EPS) trays multipacked in master bags, often barrier with internal modified atmosphere. Fresh pork has been actively converting into primary packages of poly-vinylchloride (PVC) wrapped EPS trays in master bags. But the largest segment, despite its two-decade per-capita consumption decline, has been fresh beef—nearly 9 billion packages of which are still purchased annually. This is a larger number of packages than for almost any other single food package category, reflecting the size of the target market for suppliers. And almost half of this is ground beef, the topic of so much concern relative to microbiological safety.

Today, in the back rooms of 31,000 supermarkets in the United States, butchers receive reduced-oxygen barrier bags of intact whole-muscle primal cuts or chubs of coarsely ground beef. They remove the primal cuts from the bags, cut them into steaks, roasts, etc., and package them on EPS trays that are then overwrapped with PVC film immediately prior to placement in retail display cases ill-equipped to maintain temperatures adequate for more than a few days of preservation. Coarsely ground beef is removed from its barrier chub packages and finely ground prior to packaging in PVC film–wrapped EPS trays before placement in display cabinets for perhaps up to one day of shelf life. The contemporary scenario has tens of thousands of skilled artisans whose numbers are decreasing annually in sort-of-chilled backrooms cutting, packaging, labeling, shelf placing, removing dated meat, and trying to maintain a balance of in-stock with rapidly deteriorating product.

Centralized packaging of fresh red meat means that the cutting and primary packaging take place at a site removed from the supermarket where large, sanitary, and efficient operations produce fresh meat products for dozens or hundreds of supermarkets and other retail food outlets. The objective is to deliver prepackaged red meat with several days of shelf life to retailers ready for the (display) case. By producing and packaging the meat in U.S. Dept. of Agriculture inspected factories operating under HACCP plans, safer, less-expensive meat capable of being branded is available to retailers.

Technical challenges abound in the realm of fresh red meats susceptible to microbiological spoilage and possible pathogenic microbiological contamination, and thus inherently short shelf life under the best of sanitary and distribution temperature conditions. Perhaps the most daunting is color.

Traditional retailers and meat packers insist that consumers demand a “cherry” red color characteristic of oxygenated oxymyoglobin meat pigment. This color is fleeting and obtained when the meat is exposed to air or even higher concentrations of oxygen. But high oxygen often injected to maintain red color reacts with meat lipids to alter the flavor, often for the worse. Furthermore, the oxidized version of meat pigment is metmyoglobin, which is brown and generally signals to consumers that the meat is not good. The reduced form of the pigment, seen when the meat is under reduced oxygen, is purple, also not favored by consumers, according to the “experts.”

Reduced oxygen favors longer microbiological and enzymatic shelf life and is the reasoning behind the use of barrier bags for primal cuts and coarsely ground beef in distribution to retail back rooms. Upon exposure to air, or to higher levels of oxygen, the purple color converts to red oxymyoglobin.

Other issues include the perception that consumers desire their fresh red meat packaging to be virtually the same as that from the supermarket back room, i.e., EPS plus transparent film overwrap, with little or no headspace. But the major complaint of consumers seems to be that they dis-like purge and package leakage, a common characteristic of conventional primary packaging and many of the case-ready systems.

An intriguing challenge has been to try to determine the shelf life required for commercialization of case-ready meat in the U.S. Some retailers are satisfied with just a few days, and some seem to want up to 15 days for intact muscle cuts if they can achieve it. Meat packers want to maximize the time to increase the probability of delivering good product to retailers.

There have been more than 60 case-ready systems developed, probably 30 of which are in one or another way commercial today, and about a dozen that are in real commercial use in the U.S. With so many different technologies and no means of evaluating their real merits short of actual testing, what is a packer or retailer to do in the face of so many claims of retention of microbiological and color quality?

The technologies in widest commercial use today include:

Off-site primary packaging in conventional package structures, and distribution under refrigeration in returnable crates.

Off-site primary packaging in conventional package structures and placement in master bags for chilled distribution—a significant method, especially for pork.

Off-site conventional primary packaging and placement in master bags under modified atmosphere for chilled distribution—a very significant method.

Off-site conventional packaging, placement in master bags, drawing a vacuum, with exposure to air upon opening restoring the desired red color—used for lamb and veal, with some application for ground beef.

Conventional EPS tray/PVC film packaging, placement in a gas-barrier flexible pouch flushed with nitrogen. The pouch contains an internal oxygen scavenger activated upon sealing. At retail level, the pouch is opened and the meat is exposed to air, rejuvenating the color.

Primary packaging under vacuum or vacuum skin, used mainly for prime grades.

Primary packaging in gas-barrier trays with gas-barrier heat-sealed lidding closure, packaged under high (80%) oxygen content. This system with solid multilayer barrier trays is used extensively because it is specified by Wal-Mart supercenters for their case-ready ground beef. Expanded polystyrene/ethylene vinyl alcohol lamination barrier trays are used by other chains, with barrier-foamed polypropylene trays having been introduced recently.

Primary packaging in conventional EPS trays with gas-barrier overwrap under modified atmosphere.

Primary packaging in gas-barrier trays with heat-sealed multilayer gas-barrier/ non-barrier lidding, packaged under reduced oxygen. At retail level, the outer gas-barrier layer is peeled away, exposing the gas-permeable layer through which air passes to restore the red color. This technology has several variations, including primary packaging under vacuum or under elevated carbon dioxide or injection of oxygen through a valve.

Chub packages in which ground beef is pressure packed into gas-barrier, multilayer nylon film tubes closed by metal clips. The reduced oxygen in the packages permits up to 10 days of shelf life under good refrigeration. Color upon opening is purple, but rapidly reverts to red when exposed to air.

Subprimal muscle cuts in gas-barrier bags normally used for distribution packaging. Because of the low surface-to-volume ratio, microbiological shelf life can be measured in weeks, but meat color is purple until the package is opened and the contents are exposed to air.

About 20% of all beef is case ready, and most of this is ground beef, meaning that up to 40% of ground beef is centrally packaged. Since so much chub-packaged ground beef is produced, this format, however odd it may appear in the perspective of the current situation, represents perhaps the largest single technology. It is certainly the oldest, dating to the 1960s as a consumer package. And, not incidentally, most fresh pork is centrally packaged.

So, surprisingly, the master bag with or without any alteration of internal atmosphere appears to have a larger market share at this time. Reasoning may revolve around the use of the conventional primary package that is so comfortable and credible to consumers and retail meat managers alike. Applying this reasoning means that shelf life may not be an issue with the two constituencies.

With all of its issues, high-oxygen packaging in barrier trays with barrier heat-seal lidding is strong now, largely because Wal-Mart supercenters are overwhelmingly supplied with case-ready fresh beef and pork, almost to the exclusion of back rooms. Obviously, barrier packaging cost more than non-barrier, but the total systems costs, considering the reduction in back-room labor and equipment, are equal to or less than back-room cutting and packaging.

Food technologists might ask, “With all of the technologies offered, why haven’t we had a means to objectively evaluate each on its technical merits?” Meat packers and retailers alike are confused by all the claims and counter-claims made by suppliers, and thus often are delayed in their decision making. IFT members might consider that case-ready meat technologies require both development and objective assessment, and that one role of universities is to provide services for their industry constituents, among whom are meat packers and retailers.

And the crowning question is, “Where is it all going?” As a person who in 1970 predicted complete conversion to case-ready meat by 1975, I hesitate to forecast. But the Packaging Strategies report says something to the effect that about 40% of all beef will be centrally packaged by 2005. This glimpse into the future is derived from a rational examination of the realities of technology capabilities, current equipment placements, retailer adoption rates, economics, and red-meat dynamics. But the report also asserts that a portion of the market will be captured by one or more new and as-yet-unidentified technologies. And that statement means that some food and food packaging technologists might just have some challenging research ahead of them during the next few years.

Contributing Editor
Food and Food Packaging Consultant
Duluth, Ga.

In This Article

  1. Food Processing & Packaging