Aseptic paper 'bottles' shine at California Natural Products

With 10 aseptic packaging machines, contract packaging giant California Natural Products, Lathrop, CA, is the largest low-acid Tetra Brik aseptic packager in the U.S., says vice president of operations Kevin Haslebacher.

CNP started in aseptic packaging in 1994 with two Tetra Pak machines, and it has had a special relationship with Tetra Pak ever since. In fact, nine of its 10 packaging lines are from Tetra Pak, including eight paper carton machines and a StarAsept 300-gal bag-in-box machine. "Tetra Pak has been an excellent company for us to work with. They are very sensitive to their customer's needs," says Haslebacher.

One of the shining stars for the copacking giant is the EAS AdvantEdge™ line of shakes and other nutritional beverages packed in Tetra Pak's Tetra Prisma® carton. CNP installed two Tetra Pak TBA 19 machines in 1999, and it is currently running the unique eight-sided Tetra Prisma® 11-oz aseptic carton for the performance nutrition company. The convenient, ready-to-drink AdvantEdge product is an all-natural soy, protein-based beverage that is lactose-free and contains no artificial sweeteners. It contains 15 grams of protein and only 200 calories.

Says Roger Ulane, EAS vice president of Sourcing & Materials, "EAS began developing ready-to-drink products in late 1999 to both parallel our existing powdered products and as a delivery method for new products. Product formulations required aseptic processing, and the EAS marketing department required a unique package for the new ready-to-drink products we were going to introduce. Cans and bottles were too common. Our marketing research indicated that convenience is becoming very important to consumers. The Tetra Prisma package offered that convenience in a package that was new to our market, compact, environmentally friendly, easy to carry and easy to open."

In addition to a unique eight-sided shape, one of the most striking features of the Tetra Prisma package is its metallized aluminum foil outer layer surface, printed by rotogravure rather than offset for better graphics, and laminated with a polyethylene barrier. The material, which is received in rolls, is actually a seven-layer laminate (inside to outside) of PE/DuPont's Surlyn (to provide adhesion)/aluminum foil (to provide an oxygen barrier)/PE/printed paperboard/aluminum/PE. The material is scored during the manufacturing operation so that it can be folded into its final shape in the form/fill/seal machine.

"This was a joint project with EAS, Tetra Pak, Mead Packaging and CNP," says Ulane. The product development line trials were conducted at Tetra Pak's facility in Denton, TX, and the pre-production trials to finalize the formulations were at CNP. Concurrent to the product development, the automated secondary packaging systems were being designed and integrated as well. EAS selected Mead Packaging's Cluster-Pak® 410PR system to apply the four- and six-pack wrappers, and it fed the Tetra Pak Model 70 case packer. Tetra Pak and CNP did that installation and integration with support from Mead Packaging. Also concurrent to the product development process, the EAS graphics department worked with Tetra Pak's paper production facility to produce the package graphics.

"Refining the formulations through many line trials to work well with the aseptic processing and filler requirements, and deliver excellent flavors, was a formidable task. The coordination between EAS, Tetra Pak, Mead Packaging and CNP was exceptional," says Ulane. "CNP has a great facility with excellent, well-maintained, state-of-the art equipment. They are an established aseptic processor and bring a lot of experience to the table. The production startups went very well, and the product was introduced on time."

Vf/f/s machines each run 7,500 packages/hr
The Tetra Prisma packaging material is supplied in large rolls that are mounted on the back of the machine. During operation, the material is pulled from the roll and travels up the back of the machine through a unit that punches openings for pull tabs, seals an inner patch across the opening, and then applies the foil pull tabs. This internal strip is torn away with the pull tab when the package is opened. The material then goes past a strip application station where a thin plastic strip is applied to one edge. Later in the operation, this is sealed to the other edge of the paper to form the longitudinal seam.

The material moves through a bath of 160-deg-F, 32-percent hydrogen peroxide solution. It then travels through a squeegee that removes liquid peroxide, followed by a hot air jet that blows off and evaporates the remaining peroxide. The flat, sterile material then passes over a roller at the top of the machine and begins its descent through the f/f/s section on the front of the machine.

The material is formed into a tube shape, and the edges are sealed together as mentioned previously, after which it passes around a filling tube that runs down the center of the cylinder of material. The liquid level inside the packaging material, which rises above the filling nozzle, is regulated automatically to achieve the proper fill in the package.

Reciprocating jaws, which move up and down to pull the film through the machine, close at the end of each fill cycle to form the top seal of the lower package and the bottom seal of the upper package. A blade in the center of the sealing section cuts the lower carton loose after it is sealed. The sealed but unformed cartons then pass through a final folder attachment that gives the packages their unique eight-sided construction.

Packages leave the TBA 19 in single file and are conveyed past a Domino Amjet laser printer that applies the date and lot number. The cartons then pass a Tetra Pak Model 21 vertical accumulator that stores packages if downstream equipment malfunctions. This allows the fillers to keep running without interruption. When a photocell detects cartons backed up on the conveyor, the accumulator transfers them to shelves that move upward as they are filled. When the conveyor is clear, the machine automatically deposits packages from each shelf back onto the conveyor without interfering with the packages coming from the filler.

Wraparound carton displays package
The Tetra Prisma packages are sold as individual packages and in four-packs. In the latter case, packages enter a Mead Cluster-Pak 410PR packaging machine, where a printed Cluster-Pak carton, also supplied by Mead, is wrapped around them. This carton is designed to wrap around the sides of the packages, and partially around the front and back to achieve a window effect that allows customers to see the packages inside the carton.

The Mead Cluster-Pak 410PR system was designed specifically to multi-pack the Tetra Prisma package; the Mead Cluster-Pak wraparound carton, with an ad panel, was designed specifically to enhance the unique and attractive Tetra Prisma primary container. The Cluster-Pak provides a stable package that is easy to shelve and display, and offers the outstanding billboard and shelf impact that comes with multiple paperboard packaging. Some special promotional packaging even used metallized laminated board with a UV coating to mirror the foil-like appearance of the primary Tetra Prisma container.

Infeed screws separate the single file of Tetra Prisma packages into two rows entering the machine, where they are clustered into groupings of four, and side-lug chains move them along. Suction cups on an overhead reciprocating arm swing over to pick up a wraparound carton blank from a magazine, then swing back and lay it on side-lugs traveling above the packages. The packages transfer to a bottom-lug conveyor, and stationary bars fold the side flaps of the cartons down into a vertical configuration. Simultaneously, arms fold the front and back pieces into place. The cartons transfer to side-lug chains again, and stationary bars fold the bottoms of the side flaps underneath the cartons. They also push the flaps together so that the male piece on one flap locks into the female slot on the other flap to provide a very secure package.

The four-packs are then conveyed to a Tetra Pak Model 70 packer where six of the packs are assembled and pushed onto a one-piece paperboard blank. The blank is wrapped around the packages and hot-glued. When the line is running individual cartons, the cartons are conveyed around the Cluster-Pak machine to the Model 70 machine, which assembles 24 cartons into a case. In either situation, cases are conveyed past a Diagraph PA/5000 label print-and-apply machine that prints bar-code and production information on a pressure-sensitive label, and applies it to the case. Cases are then hand-palletized.

Robotic palletizers
CNP has two robotic palletizers from ABB handling other products and has plans to add two more. Each palletizer is set up to handle product from two packaging lines so one of the new units would be dedicated to the two Tetra Prisma lines. In the palletizing operation, a small, rail-mounted car picks pallets from a magazine and delivers them to the palletizers as they are needed. After a pallet is in place, the palletizer picks cases from the two infeed conveyors with suction cups and places them on the pallet. The unit can handle up to four cases simultaneously. But, if sensors indicate that fewer are present, it only activates the suction cups that are needed for those cases.

The robot's control system keeps track of the number of cases that have been placed on a pallet. When a full load has been assembled, the arm raises out of the way, and the pallet discharges onto a rail car on the other side of the machine that transports it to an ITW Mima stretch wrapper. This overhead-style machine has a carriage that rotates around the pallet to apply the stretch film. Pallet conveyors and controls were supplied by Hytrol Conveyor Co.

More information is available:

F/f/s machines, accumulators, case packers, packaging material: Tetra Pak, 847/955-6000. Circle No. 244.

Packer, cartons: Mead Packaging, 404/897-2144. Circle No. 245.

Printers: Domino Amjet, Inc., 708/244-2502. Circle No. 246.

Label print/apply: Diagraph Corp., 314/739-1221. Circle No. 247.

Palletizers: ABB Flexible Automation, 800/804-5417. Circle No. 248.

Stretch wrapper: ITW Mima, 800/662-6462. Circle No. 249.

Conveyors, controls: Hytrol Conveyor Co., Inc., 870/974-5642. Circle No. 250.

Surlyn film: DuPont Packaging & Industrial Polymers, 800/438-7225. Circle No. 251.