Retort packaging 90 degree peel and lid strength testing

  • Mecmesin

The food packaging industry has long had concerns about pinholes, flex cracks and leaks in the flexible materials and seals of retort flexible lidded packaging. A famous global food and drink maker needed to test the laminated retort (and other thin film) packaging solutions that protect products such as their popular microwaveable stir-in pots.

Retort film is manufactured from multiple layers of laminate foil and withstands extensive thermal processing to heat seal and sterilise food contents. This packaging method provides the product with shelf-stability, while giving consumers convenience and protection from harmful microorganisms.

Solution

Since blown seals or breaches in film can lead to contamination or spoiling that can cause food poisoning, this maker needed to run peel tests to determine the following:

  • tensile strength of pre-cut retort foils
  • peel performance of finished packaging
  • compliance of tensile and peel performance with in-house specifications

To obtain a reliable picture of the performance of their packaging seals, this maker selected a Mecmesin computer-controlled test system fitted with a custom-designed pull-peel table.

The Mecmesin system enables a 90 degree peel test. The pot-shaped container is secured and fixtured to an assisted peel table, and the container's foil tab is held by a flat-faced jaw grip. The table moves the container horizontally, against the direction of peel, at the same rate as the grip pulls the foil tab upward (150 mm/min). These synchronised motions cause the foil to be steadily peeled away at a constant 90 degrees. The test stops when the foil is fully separated from the container. The advanced MultiTest 1-i system uses Mecmesin's Emperor™ force testing software running on a PC to record and display the performance of the sample during the test. Peak force is identified and a detailed graphical display of each test is presented, enabling identification of defects and locations of adhesive failure.

The flexible container must be gripped in a consistent manner with no deformation, in order to maximise the repeatability of the test. Mecmesin recommends use of a custom-designed vacuum fixture matched to the packaging geometry, in order to contact the container evenly around its entire surface.

The result is improved consistency in adhesive application and foil-container seal quality, which lessens the likelihood of customer grievance and wastage.

Test equipment

  • MultiTest 1-i computer-controlled test frame rated to 1000 N
  • Assisted pull-peel table
  • Flat-faced jaw grip
  • Emperor™ software
  • Container holder, custom-designed vacuum-operated recommended.

Images: Retort flexible lid peel test and assisted-pull table fixture, assisted-pull peel table mounted on a tensile tester and vacuum container fixtures.

See also

Cosmetic packaging pull-off test

Cosmetic packaging pull-off test

A bench-top testing system was required to repeatably test the pull-off force on a variety of cosmetic containers. The system needed to allow a relatively high volume of containers to be tested with the minimum level of training required for users. Mecmesin's solution avoided the risk of damaging the loadcell by excessive torque on tightening the collet grip, and the lipstick barrel was first inserted in the grip and then connected to the gauge by a flexible chain-link.

Ice cream container lid closing effort

Ice cream container lid closing effort

Food packaging made from thermoformed plastics and intended for freezing, requires testing to ensure optimum functionality when closing and sealing the container. The closing effort of the lid is measured by using a motorised force tester controlled by software together with a custom-designed fixture to hold standard-sized ice cream tubs. In addition the ‘top-load’ crush strength of the container itself can also be tested on the same machine to guarantee it is rigid enough to avoid buckling and spillage when the lid is applied.

Mecmesin develops Combi Cork-i Extraction Tester for leading Scottish whisky

Mecmesin develops Combi Cork-i Extraction Tester for leading Scottish whisky

To improve the quality and storage of a premium product, the R&D team at a leading Scottish whisky maker needed to optimise the design of their bottle stoppers. They decided that the strength and performance of their reusable stoppers could be ensured by systematic testing of the characteristics of both portions of the stoppers. Working closely with the R&D team, Mecmesin developed the Combi Cork-i Extraction Tester, an innovative multi-function cork extraction testing system that tests both phases of de-corking synchronously.

Greek beauty product manufacturer guarantees production quality by updating to Mecmesins digital torque testers

Greek beauty product manufacturer guarantees production quality by updating to Mecmesin's digital torque testers

A manufacturer of a wide range of skin, hair-care, make-up and sun-care products based in Greece needed to replace their outdated torque testers with up-to-date digital torque testers to guarantee production quality and to ensure their products remained sealed. Mecmesin supplied the company with two Tornado 10N.m digital torque testers, which have the ability to test tamper-evident closures, an intrinsic part of their specification.

  • Jo Webb
  • Product Info
  • English
  • Created 06 Jun 2019
  • Modified 11 Jun 2019
  • Hits 216