required to open a peelable package had to be within a defined
range, as determined in a series of technical tests and based on the
findings of the two consumer tests with healthy people and people
with hand disorders, performed by Schreib and Liebmann (2011)
and Marks et al. (2012), respectively. Bell AG obtained this
optimal range by adjusting the parameters of temperature, pressure,
and dwell time of the sealing process for each packaging
machine, in such a way that the packages were easier to open while
still ensuring that the contents remained safely wrapped. The
sealing seam and its tear contour were also changed in order to
provide an optimal and jerk-free force distribution during the
opening process. A forward tear contour has a favorable effect on
the peeleline profile. Thirdly, the size of the tear tab exceeded the
threshold of 10 mm in length, providing as large a contact surface
between the fingers and tab material as possible and allowing the
use of the key grip to exert greater force (Fig. 2). Quality management
procedures have been introduced to ensure that daily production
complies with the new specifications. For example, the
force required to open the packaging is tested periodically using a
specifically designed device.
In a pilot study, we tested three types of the modified peelable
meat packages produced using different sets of sealing parameters.
Ten patients (six women, four men) with hand disorders and a
mean age of 63 years were asked to open these packages. All the
test packages looked exactly the same: size, content, cover, and
laterally placed notch. The only differences were in the abovementioned
sealing parameters. The patients opened all packages
in their usual way and without aids. The opening process was
filmed with a video camera so that any difficulties with the packaging
could be evaluated objectively. Each time they opened a
package, the patients completed a questionnaire about their subjective
difficulties in opening it, including the seal, tear tab size, tear
tab palpability, visibility of the opening mechanism, force required,
pain during the opening process, and problems with the fine motor
skills. The patients also evaluated the laterally placed notch. Based
on the results, we adapted the packaging and decided what technical
configurations would be the best for the patients, bearing in
mind that the contents always have to be packed safely.
In the next step, reported in the present paper, we carried out a
larger study to determine whether patients were more satisfied
with this technically modified packaging (Type B) than with the
packages that were available in supermarkets at that time (Type A)