The question may seem simple: can you open it or not? But the test methodology currently favoured by the committee working on a European standard (CEN) for packaging openability has turned out to be a can of worms.
A new report compiled by three Scandinavian research organisations underlines the value of sensory analytical testing for openability. Using trained panels, and traditionally applied to organoleptic testing, the sensory approach gives a fuller picture than alternative techniques, says research partner the Swedish Institute for Food and Biotechnology (SIK).
Senior consultant at SIK Annika ström admits that mechanical testing, which simply measures the force required for an operation, is repeatable and relatively cheap. "But it gives a very narrow picture, and cannot be used if you want to predict easy opening." It is more applicable to quality control, say some experts.
The results of 'descriptive sensory profiling' go well beyond single measurements, ström argues: "They shine a light on the totality of a product's traits and qualities."
Those involved with the project had hoped that its results would contribute to current work on an EU standard on pack openability. But at Finland's VTT research centre, senior research scientist Raija-Liisa Heiniö says: "The CEN Standards Committee didn't want to wait for the results of our two-year project."
Instead, the committee went ahead with work on a standard which favours a third approach to testing: consumer panels, comprising untrained individuals.
"They should have waited for our results," says Heiniö. "And they should demonstrate that this test method has been scientifically validated. Unfortunately, they haven't done that yet."