Karsten Thurling, a researcher based at the Fraunhofer Institute for Process Engineering and Packaging IVV in Freising, said that round robin test will be used to verify a method generated by an institute-led research project, ‘Easy opening of peelable packages’, that it is hoped will inform the German or European standard for the determination of peel and opening forces for peelable packaging.
He added that a draft of the test method, which was based on experiments with children, adults and the elderly, was submitted for review to the German packaging standard committee last month.
Speaking at the Pro Sweets trade show earlier this month, Thurling said that the focus of the Fraunhofer project was the assessment of user-friendly opening forces such as pull tab or sealed seam design and stability for the second hand.
The research project, whose ultimate goal is to provide a systematic representation of the effect of these design criteria on handling characteristics of packaging to both optimise and speed up packaging development, involved packaging material and equipment companies as well as food manufacturers such as Nestle and Muller.
In terms of flexible packaging such as tubular bags and thermoformed formats, Thurling said both hands are active and move approximately symmetrically, and the tear angle used in the Fraunhofer test for flexible packaging is 180°C at a testing speed of 600mm per minute.
The results of the research with the different age groups shows the maximum force applicable by human hands on plastic (OPP40PEpeel90) with a 14mm long tear off flap was 10 newtons for children aged 8-10, 17 newtons for adults aged 20-60 and 11 newtons for elderly persons aged 61-80.
Thurling said packaging has to meet a variety of requirements but opening behaviour is crucial for consumers in terms of product acceptance, with factors such as user-friendliness and an ageing society crucial for informing design considerations.
Recent surveys have shown how important it is to devote more attention to easy opening. According to a study carried out by the Fraunhofer Applications Center, easy opening is becoming a key product differentiator, particularly among older consumers.
If a package is difficult to open or if the film suddenly tears apart, 54 per cent of the people asked said that this would be a reason for not buying the product the next time they went shopping, and that they would then prefer to try out a different item. This response makes retailers, food suppliers and packaging manufacturers sit up and take notice.