Rigid plastic packaging manufacturer Amcor Rigid Plastics has developed a hot-fill PET container which accepts metal lug closures, said to be a first for the food packaging industry. The breakthrough technology is called the A-PEX63 system.

The technology allows the fitting of metal lug closures to blow-and-trim 24 oz hot-fill containers. Thus, consumers who are familiar with the look and quality feel of a glass jar with a metal lug closure can now enjoy the same quality and reassurance of the fresh “pop” of a metal lug closure on a lightweight, shatter-proof PET jar. Australia-headquartered Amcor says the A-PEX63 system ensures that sealing integrity is maintained and meets the industry average for removal torque (ease of opening). Brand owners can also maintain the same brand equity with the switch from glass to PET.

The patent-pending technology was achieved through the use of advanced design and engineering techniques, according to Bunlim Ly, Senior Marketing Manager for Amcor Rigid Plastics. “This is a major development which firmly positions PET hot-fill containers in the food packaging industry,” said Ly. “We’ve filled an important need for consumers and brand owners who seek the benefits of PET containers with metal lug closures, delivering the same quality and freshness associated with glass along with significant performance, manufacturing, and sustainability benefits.”

The enabling technology creates “a paradigm shift” for the food packaging industry from conventional glass with metal closures to plastic with metal closures, according to Peter Bates, Amcor’s senior R&D engineer who worked closely on the technology. “This is a unique solution which mimics glass in its acceptance of metal closures while also providing all the inherent benefits of plastics,” said Bates.

Targeted for food applications such as jams, jellies, salsas, apple sauce, and pesto sauce, the containers are a drop-in solution for manufacturers and provide reduced carbon footprint. The shift to A-PEX63 PET containers requires no capital investment and can be adapted to existing capping and filling equipment. Furthermore, the containers sport a 63 mm finish with a functional “pop” tamper-evident indicator button on the closure. The "pop" that consumers hear when opening a jar has long been associated with freshness and product security. The containers are also hot fillable up to 96°C and available with Amcor’s Powerflex vacuum absorbing base for those applications that require enhanced vacuum performance.

Among PET’s key sustainability benefits are a 36% energy savings and a reduction of 2,024 tonnes of CO2 emissions, which is equivalent to electricity use for one year for 278 homes. Versus the 330-g glass container, the 51-g PET container results in an 85% material reduction per jar. The weight reduction results in major transportation cost benefits including the shipment of 30% more product by weight per truck.

A recent consumer focus group conducted by Amcor showed that A-PEX63 containers maintained a product’s brand equity and reassured consumers about freshness. Consumers also liked the “pop” feature, the reduced weight, and the easy-to-grip, easy-open feature. The hot-fill containers also passed distribution abuse testing including variation, impact, and 5-ft vertical drop evaluations.

Amcor says it has conducted extensive lab scale and line trial testing to prove the technology. The containers are commercially available for food manufacturers throughout the US. Amcor is also evaluating the potential of expanding the technology to include 16 oz and 48 oz containers for similar hot-fill food applications.