By David R. Stone
Hormel Foods Corp.'s marketing department gave a simple-sounding assignment to its engineers and suppliers: redesign the packaging of a few sliced meat products so customers can reseal the package.
Yet, it took much effort by Hormel R&D personnel, working for more than a year with Multivac on the equipment, American National Can on the packaging film and Zip-Pak on the zipper, to get the new, reclosable "pillow pack" packages into production. The hard work was worth it-sales have grown, and the package won this year's National Flexible Packaging Association award.
A major component of the new package is a Zip-Pak "zipper," which is automatically affixes to the rollstock film by the horizontal packaging machine. Some of the engineering problems were solved when this reclosable seal, jointly patented by Oscar Mayer Foods Corp. and Zip-Pak, became available for licensing and use by other food companies.
Mark Coffey, Hormel product marketing manager, says the zipper pack is being used for nine retail pre-sliced products, including: Italian dried salami, Genoa sausage, large and small diameter pepperoni, dried beef, Homeland hard salami.
Three new items are cut into julienne strips and packaged under the Light & Lean 97 line-ham cuts, turkey breast (oven roasted), and smoked turkey cuts.
In addition, the large pepperoni and Genoa sausage are offered in a larger foodservice package, with the same zipper feature on the package.
The package is produced on a Multivac R7000 thermoform/fill/seal system, outfitted with an in-line zipper profile applicator. It produces four packs at a time and can operate as fast as 16 to 17 cycles a minute, according to Dan Miller of Hormel's packaging engineering department.
Hormel currently has three of the units in operation; Multivac made some equipment modifications specifically for Hormel. The newest line, the Lite & Lean 97 Meat Cuts, is operating at far below the equipment's rated speed because product is being manually loaded. The reason is that an automated loading system is a "significant capital investment," Coffey explains. Hormel is "testing the waters" in terms of sales volume before making the investment.
Yet, there already has been a considerable investment of time and energy just to create the package. Miller, one of the engineers involved in developing the packaging film "substrate," said it took about a year to develop the packaging for the sliced pepperoni, salami and dried beef.
The package uses a clear forming film on the bottom and a printed film on top, Miller says. Pepperoni and other products packaged in this new film reached the market in April 1992. The newer Hormel Cuts reclosable package took an additional six to eight months to develop, he notes. These packages are printed on both top and bottom.
To achieve the desired result-an attractive package with appropriate barrier and abuse-resistance properties, sealability, etc.-American National Can and Hormel created a new packaging substrate. For the Lite & Lean 97 line, they use a seven-layer forming film, 7-mil thick. It includes 2 mil of nylon on the outside of the package, with 15-pound low density polyethylene (LDPE) and a 5 mil EVA sealant. The top film is constructed of 72-gauge, saran-coated, biaxially oriented nylon on the outside, 15-pound LDPE and 2 mil of easy-peal sealant on the inside.
(Although the laminated substrate was developed for Hormel, American National Can's Joe McGowan, marketing manager for meat packaging, said it is available for use by other meat processors.)
The retail packages measure about 4-by-4.5 inches, except for the foodservice packs-which are about 4-by-8 inches.
When packing the Lite & Lean meat cuts, the Multivac machine creates a pocket with a forming depth of 1.75 inches; for the sliced salami and pepperoni products the forming depth is 2.875 inches. The deeper pocket requires a heavier forming film than the Lite & Lean 97 items, so a 9 mil forming film is used.
In production, flexographically printed rollstock film is formed into pockets, the product is inserted, the zipper is fed, the top film is applied, the first seal is made, and the package is backflushed with nitrogen as it is fully sealed. (The Multivac machine is also capable of vacuum-sealing.)
It is quite an engineering feat to create such a deep pocket and still maintain all the layers in such precise register that the printed bar code can be easily scanned at the supermarket, Hormel's Miller points out.
To accurately advance and register the top and bottom films, the machine has a photo-eye that reads a special mark printed on the film.
At Hormel's plant in Algona, Iowa, where the pepperoni product is produced, the entire process is automated.
Carl Hachbert, a Hormel senior staff engineer, said the production line previously required seven employees and operated at a rate of seven cycles a minute. By eliminating hand-loading and hand-scaling, Hormel avoided the need to add a production line when demand for the product began to grow.
The line now produces 68 products a minute (17 cycles, with four packages at a time), with eight employees. The equipment required a considerable investment, Hachbert said, but "the payback has been profitable."