Rotary process gives better results in barrier and retort

Unlike traditional thermoforming, RTF bypasses the sheet stage. Tulip's category manager for packaging materials Mette Garugaard said: "When you retort plastic, it will typically try to return to its original form and we want to sell our pork luncheon meat in tubs, not sheets!"

According to Rexam, improved material distribution in the polypropylene pots means that the same proportion of barrier ethyl vinyl alcohol can give improved performance and longer shelf-life. As Garugaard put it: "Given our demand for a two-year shelf-life, we had to be on the safe side with high barrier." Tulip also supplies the same products in cans.

Tulip's pots are heat-sealed and made reclosable with an injection-moulded lid. But Rexam's European sales and marketing director for food containers Nick Brewin explained: "The design means that, in other cases, the container can be double-seamed with a metal end. This is unique to Rexam, and is our biggest selling point."

Rexam in the US also produces RTF barrier packs for Princes, Isabel in Spain and Nestlé Germany. Within three years it hopes to establish a European multilayer RTF site.