The steel can still can

The easy-open ends on cans of Capitaine Cook tuna salad are made from a peelable aluminum lid stock from Crown Holdings. Consumers eat directly from the bowl-shaped container.

Capitaine Cook of Plozevet (Brittany), France, uses a different style of easy-open end for its tuna salad products. The company closes its steel cans with peelable foil instead of a metal end. The consumer pulls a tab to remove the foil, then eats the salad directly from the bowl-like can.

The peelable can “end” consists of a thin, flexible panel heat-sealed to a metal ring; the ring is flanged to run on conventional double-seaming equipment. The peelable material is aluminum foil, laminated with polypropylene film on the inside and lacquered on the outside. Crown Holdings supplies Capitaine Cook with the peelable can ends under the Peel Seam trade name.

Recloseable cans

A separate innovation, also driven by the demand for convenience, is the recloseable steel can. Hirzel Canning Co. (www.hirzel.com), Toledo, Ohio, was the first U.S. company to switch to it. Hirzel fills its Dei Fratelli Presto! brand Italian dip and pizza sauce in the container.

The can’s closure features a vacuum-release design. The user pulls back the pressure-release dot on the lid, releasing vacuum from the can, and lifts off the closure. The lid snaps back on the can for product storage. This Dot Top lid is supplied by Silgan, which licenses the closure technology from Metalgrafica Rojek of Brazil.

The cost of the recloseable 12-oz. can is 15 percent higher than a conventional can, or roughly two to three cents more per can. However, the package is less expensive than a glass jar with a lug cap. In addition, Hirzel’s recloseable can-filling line runs 30 to 40 percent faster than a jar-filling line.

Because the new can positions Dei Fratelli Presto! as a premium brand, the company is able to suggest a retail price that is about 15 percent higher than if the product were filled into a standard 15-oz. steel can.

Hirzel Canning intends to launch additional products in the recloseable can. “We think there’s some opportunity with dipping sauces and other spreads; international products, everything from Sicilian sauces to Vietnamese and Far Eastern; and even something like value-added pasta sauces,” says President Steve Hirzel.

Self-heating and microwaveable

Beverage fillers are leading the way with a convenient “can” of a different sort, a self-heating can that combines plastic and metal. WP Beverage Partners LLC, Newport Beach, Calif., recently introduced Wolfgang Puck gourmet coffee in a retortable, self-heating can developed by OnTech Delaware Inc. and manufactured by Sonoco Products Co.

Lakeside Foods Inc., Manitowoc, Wis., plans to launch Hillside brand flavored-coffee products coffee in the same container later this year. Although the first commercial applications are beverages, the self-heating container also could be used for soup. The container holds 10 fluid oz. of product.

Lakeside Foods will soon introduce Hillside coffee products in the self-heating “can” developed by OnTech Delaware Inc.

The body of the container consists of a blow-molded, polypropylene cup and inner cone. The top is a steel stay-on tab (SOT) end, and the bottom is a pop-top, full-panel steel end that provides tamper evidency and protects the self-heating mechanism until time of consumption.

To start the heating reaction, the consumer pushes the activation button on the bottom of the container. This lets calcium oxide and water in the package’s inner chambers mix, generating heat. The coffee, in an outer chamber, heats to about 145 degrees Fahrenheit in six to eight minutes.

Another self-heating can technology, not yet in commercial use, takes a somewhat different approach. The self-heating mechanism also uses chemicals to create an exothermic reaction; however, the chemicals are contained in a pocket between the steel can and a polypropylene or high-density polyethylene (HDPE) outer sleeve that encases everything except the top of the can.

After pushing the activation button on the bottom of the can, the chemicals mix to create circulating steam that continues to heat the food for 30 to 40 minutes. The food heats to 150 degrees Fahrenheit in three to four minutes, with no steam escaping from the container.

This technology is designed for use with standard steel cans fitted with easy-open, pop-top ends. The application of the plastic sleeve and self-heating chemicals occurs after the can has been filled on a conventional canning line.