Laser Perforation Revolutionising
Intelligent Packaging
aser microperforation is
revolutionising the food
packaging industry, driving
forward the advancement
of intelligent packaging
solutions. From extending the shelf life
of fresh produce, to making it possible to
microwave a pre-prepared roast dinner in
minutes, these microscopic holes are quite
miraculous. Here, Steve Hughes, managing
director of REO UK, takes a look at how
laser microperforation is evolving food
packaging and why maintaining accuracy
is vital to success.
L
When it comes to designing food
packaging there is more to take into
account than the point of sale (POS)
appeal. Consumers are becoming
increasingly savvy and they want more
value for their money than produce that
is going off before it’s even made it from
car boot to refrigerator. In addition, calls to
put an end to food waste are becoming a
common sight in international headlines,
and packaging that extends the life of
produce will go a long way to answer this
call.
Waste not, want not
According to the United Nations
Environment Programme (UNEP), around
one third of food produced globally for
human consumption each year is wasted.
That’s about 1.3 billion tonnes. In the
United States alone, 30 per cent of all food
is thrown away every year.
Well designed intelligent packaging can
not only help consumers in choosing
the right amount of food for their needs,
it will also keep it in the best possible
condition for longer. This has led to a
wave of research and development that
has contributed to the increasing use of
laser perforation technology in a variety of
applications.
Breathability
In 2013, The Co-operative group of
supermarkets in the United Kingdom
started using computer-guided laser-cut
modified moisture packaging (MMP) for
its packaged tomatoes. The small hole
perforation technology extended the shelf
life of the fruit (yes, tomatoes are a fruit!)
by two days.
This is because the precise holes in the
packaging allowed the tomatoes to
continue to respire, i.e. draw oxygen in
and release carbon dioxide. Without the
right balance of perforation, the packaged
tomatoes would either become too dry or
would decay and develop mould.
52
PECM Issue 17
ASDA addressed the same problem with
its Extra Special Cornish Crystal Potatoes
by working with Ultimate Packaging to
develop packaging that employs laser
perforation patterns to optimise gas
transmission through the film. As a result,
ASDA reported a 92 per cent year on year
reduction in customer complaints.
Revolutionising dinner time
The accuracy of laser microperfo ration is
also driving evolution in the preparation of
fast-cook oven and microwave meals. For
example, Dutch food manufacturer Qizini
has been exploring revolutionary variable
heat steaming methods in its packaging.
While the low density polyethylene (LDPE)
material of the film lid plays a role in the
effectiveness of this particular packaging,
it’s the minute and exact perforations
over the two individual compartments
that are the key to success. The ready
meals are packaged with vegetables in
one compartment and meat in another
and the distribution of three sets of
microperforations, combined with small
LDPE pressure sensitive labels, allows for
both to cook properly in the same amount
of time.
As laser perforation is so precise, the
intensity of steam and pressure in each
compartment can be controlled so that
the protein compartment is cooked
thoroughly in the same amount of time it
takes for the vegetables to be cooked.
Accuracy
Perforation in food packaging isn’t
something that’s necessarily considered
new, but for a long time it has been a
one size fits all solution. However, laser
perforation means
that now things can be
optimised for individual
requirements with great
ease.
Such is the appeal of
bespoke perforation
solutions that food
packaging companies
are investing heavily
in laser perforation
technology. For
instance, in 2014
Clondalkin Flexible
Packaging invested
£400,000 on new
machinery, including
a laser perforator to
enhance the quality
of perforations in its
pre-cut lids that are
regularly used on multipack products such
as yoghurts.
When spending heavily on new
equipment, to benefit from its accuracy
levels, it’s important to ensure you’re set
up to keep those levels as high as possible.
Despite the use of new generation laser
technology, many applications are still
using conventional power supplies that
are not suited for the high frequency,
highly capacitive load placed on the power
supply.
This causes power quality problems
including voltage fluctuations, unwanted
tripping and dips in output voltage, which
leads to a drop in laser power resulting in
poor process performance. The aim of the
game is to consistently achieve very small,
well defined, uniformly spaced holes.
Disruptions to power quality will have a
detrimental effect on this goal.
That’s why we've designed the REOTRON
SMP to specifically overcome these
problems by creating special control
algorithms for use with capacitive loads.
This means that you can maintain voltage
and current along with a high level of
accuracy. By overcoming power quality
issues anyone using laser perforation
is sure to continue to benefit from the
capacity for faster product throughput and
low reject rate.
So if you are looking to get the most
out of the revolutionary nature of this
laser technology, it’s important to make
sure you have the right infrastructure to
support the accuracy it is so renowned for.
www.reo.co.uk