Used in Europe for the past two years a foamed polypropylene and ethylene vinyl alcohol material called TiroMap is beginning to make its mark on this side of the Atlantic. First in the U.S. to use the material is Burnett and Sons of Monrovia CA. On a horizontal thermoform/seal system Burnett thermoforms trays of TiroMap to use as secondary packaging for one line of beef items and another line of pork cutlets. Raw meat products are first vacuum packaged in a proprietary barrier material on a separate form/fill/seal system then cooked in-pack. This pack is then loaded into the TiroMap tray to which a flexible-film lidding material is applied. The chief benefit of the tray is that the food can be microwave-reheated in it. Previously Burnett thermoformed a flexible film for the bottom component of its secondary packaging. Consumers were instructed to discard this outer packaging material and microwave the food in its primary package for six minutes after punching a few small holes in it. Then came the hard part: cutting the bag open and serving the hot food. "It was not at all user-friendly because you had to squeeze the two-hundred-degree meat and gravy out of the bag" says Burnett's Tony Luna. "Now you squeeze the product out of its bag while it's cold and heat it in the tray. You can even serve from the tray. It's much more convenient." Developed by TiroPak a division of Convenience Food Systems (Avon MA) TiroMap is produced in TiroPak's Romont Switzerland facility. In Burnett's case a layer of polyethylene sealant is added to give the 17"-wide sheet a thickness of 49 mils. TiroPak isn't providing precise details on how it produces the structure though company literature describes the use of a "natural blowing agent" on the "world's largest in-line barrier foam extrusion line." TiroPak emphasizes that the foamed PP/EVOH/PE construction is created via an in-line process. While retaining the familiar feel of expanded polystyrene TiroMap can be microwaved at temperatures to 90°C (194°F). TiroMap is also positioned as a "green" alternative because says TiroPak it requires less polymer than standard structures it has replaced in Europe including PS/EVOH/PE polyester/PE and polyvinyl chloride/PE. Another important advantage to Burnett is the rigidity of the tray. Compared to the flexible package it has replaced it displays far better in the refrigerated case. "The previous package didn't display well at all" says Burnett president Don Burnett. "The switch to a more rigid and squared-off secondary package means items can be stacked four or five deep behind a single facing." Why barrier films? Like the flexible material it replaced the tray and lid perform a valuable back-up role: Should the cook-in bag leak there's a second package to catch the liquid and avoid a mess. Considering that primary packaging contains a high barrier it would seem unnecessary to include costly EVOH in the foamed PP tray. The 2.5-mil nylon lidstock from Cryovac (Duncan SC) also has a gas barrier component: a coating of polyvinylidene chloride. And to complete the picture Burnett evacuates and backflushes the tray with a mix of nitrogen and carbon dioxide commonly found in MAP applications. According to Burnett all of these measures represent an "insurance policy." "The cook-in bag as it makes its way to the secondary package could easily get contaminated in some way" Burnett explains. "Sauce or gravy for example could be spilled on it. If I put that item in the tray and don't have a barrier to oxygen and don't gas flush the organisms on the outside of the bag could start growing. Should that happen it could cause an off odor to develop which would make the consumer think the meat inside the primary package is bad." Though superior to its flexible-film predecessor in many ways the new packaging format does have one drawback: It takes longer to form than a flexible film. Output says Luna has decreased by anywhere from 30% to 40%. For that reason a second thermoform/seal machine is on its way. Its arrival will undoubtedly help greatly in Burnett's pursuit of private label business (see sidebar right). Until it arrives Burnett will continue putting some of its 10 items in the old package format. All new accounts however get the new tray. One thing that hasn't changed much is cost of materials. "The two formats are very comparable in that regard" says Luna. It's possible that the cost of TiroMap will come down if the U.S. customer base expands enough to warrant a TiroPak facility here. Luna adds that some equipment costs were incurred as the thermoform/seal system from another Convenience Foods division called Tiromat was modified to handle the more rigid forming web. Burnett added a sandwich preheat station a plug assist to aid in forming and cutting tools that round off the otherwise sharp edges of the packs. Burnett produces its packages two-up at about 16/min. Refrigerated shelf life is 55 days Refrigerated shelf life of the random-weight items is 55 days same as it was in the former packaging format. Burnett applies a sell-by date but store personnel do their own weighing and pricing. Stores in most parts of the country carry the Burnett line which can be priced from $3.39 to $5.29/lb. Typical portions weigh anywhere from 13/4 to 21/2 lb. Luna views the commercialization of the TiroMap material in the U.S. as the next logical step in the ever-expanding growth of the category known as home meal replacement. "When fresh fully cooked foods like this can be microwaved and served in this kind of convenient format that's the key" says Luna. Owner Don Burnett is excited about the new package too though he does point to one hurdle all home meal replacement providers have to clear: perceived value. "The consumer is still reluctant to pay more for what appears to be less" says Burnett. "They see raw meat as better value because it's twice the size. What they forget is that when they cook raw meat they lose 45 percent of its weight in the process." Burnett sees this kind of value-added program as one way to boost the fortunes of the beef industry which lags considerably behind the poultry crowd in the amount of fresh fully cooked branded items it offers. So is Burnett simply stealing a page from poultry's book? Not really he says. "We're writing our own book." And it's a book in which packaging technology is a dominant character.