Food "Tattoos" an Alternative to Labels for
August 31, 2009
Those small and sometimes
inconvenient sticky labels on produce may eventually be replaced by laser
tattoo technology now being tested by
Agricultural Research Service (ARS) and
University of Florida (UFL) scientists.
Called laser etching, the new technology puts a tattoo on grapefruit and
other produce so it can be identified at the supermarket checkout lines. The
technology was invented by former UFL scientist Greg Drouillard, now with
Sunkist Growers. Grapefruit has always
been labeled with sticky paper labels that mar the fruit and stick to one
another in storage. The labels are also easily removed, making it more
difficult to track a piece of produce back to the source if the need arises.
Narciso at the
Citrus and Subtropical Products Laboratory in Winter Haven, Fla., and UFL
researcher Ed Etxeberria investigated laser technology as an alternative to
sticky paper labels.
A carbon dioxide laser beam was used to etch information into the first few
outer cells of the fruit peel. The mark cant be peeled off, washed off or
changed, offering a way to trace the fruit back to its original source. This
permanent etching into the fruit peel does not increase water loss or the
entrance of food pathogens or postharvest pathogens if the laser label is
covered with wax.
Further testing shows the wax may be unnecessary, since the tiny holes
etched into the grapefruit peel are effectively sealed by the carbon dioxide,
preventing decay and food pathogen entry. However, wax coverage is recommended
to eliminate water loss. In testing for fruit decay, the fruit was inoculated
with decay organisms and then etched with the laser. No pathogens were found in
the peel or the fruit interior.
Narciso and Etxeberria found that the laser cauterizes the peel, much like
when a laser is used on human skin. The cauterized area is impenetrable to
pathogens and decay organisms and resists water loss. Testing is also being
conducted on tomatoes, avocado and other citrus fruits. The process would have
to be approved by the Food and Drug
Administration before it could be used commercially.
This research was reported in the scientific journal HortTechnology.
ARS is the principal intramural scientific research agency of the
U.S. Department of Agriculture.