« December 2007 Table of Contents
Processing & Services: Extending shelf life
Processors turn to packaging to reduce shrink, add convenience to RTC seafood meals
By Lauren Kramer
December 01, 2007
Consumer demand for convenient meal solutions has increased
the need for packaged foods that provide an easy-to-cook meal.
Retailers and manufacturers are turning to eye-catching
packaging to sell ready-to-cook seafood products as well as to
the product's shelf life and reduce shrink.
A decade ago, modified atmosphere packaging (MAP) was touted
as the packaging technique of the future for the seafood
industry. The system involves replacing air in a package with a
mixture of different gases in order to regulate microbial
activity and reduce the product's deterioration. But today
there still are only a handful of seafood processors using this
That's because of the Food and Drug Administration's
stringent regulations, says Barbara Blackistone, director of
scientific affairs at the National Fisheries Institute. Should
processors use MAP, controls such as breathable film and time
temperature indicators (TTIs) must be used to avoid the
potential outgrowth of Clostridium botulinum - botulism.
"The industry has not chosen to employ these controls to
much extent, so MAP has not been a popular method for packaging
seafood," she says. "Some say TTIs are unpopular with consumers
because the color change is hard to interpret."
The cost of TTIs could be another reason for avoidance of
MAP packaging in the sea-
food industry, says Brian Fortune,
president of Atlantic Aqua Farms in Prince Edward Island,
Sealed Air's Cryovac Food Packaging is one company offering
two MAP programs for seafood. The BDF 2060 film is a shrink
film alternative that creates an oxygen barrier and is a
resistant to punctures, tears and abrasions.
"The atmosphere of 70 percent nitrogen and 30 percent carbon
dioxide will result in a quality life of the product for most
species of 10 to 12 days," says Jim Belcher, director of
case-ready marketing for the company. "But this is always
contingent on the age and quality of the fish when packaged,
and the temperature of the product during distribution and
The major advantage of BDF 2060 film is its ability to run
multiple tray sizes with minimal change-over time on the
processing line and still achieve a product that looks similar
to an in-store overwrap, Belcher says.
Cryovac's lidstock and barrier tray package, together with
gas flushing, is the second MAP option. The system creates a
low-oxygen atmosphere with an oxygen-barrier layer to maintain
the gas mixture, combined with two internal abuse layers for
additional protection. The lidstock hermetically seals to the
pre-formed barrier foam tray during the packaging process.
"This style is easy to run and the equipment costs can be
less for the small processor, though changing tray sizes is a
little more difficult," Belcher says.
In addition, processors
can choose from a large selection of barrier trays.
Both systems require TTI labels that inform retailers if the
product has encountered fluctuations in temperature during
transport or display. When activated, the TTI sensors change
color from yellow to pink depending on the product's
While the TTI labels meet Food and Drug Administration
guidelines for MAP packaging of fresh seafood products, they
can be an expensive addition to the packaging process. "We
don't have a lot of customers using this, perhaps a dozen or
so," admits Belcher.
Without the TTI labels, a machine that enables MAP can cost
$35,000 for 10 packages per minute, and up to $250,000 for
high-end equipment. "How long it extends the shelf life really
depends, but if everything is done right and the temperature is
controlled, you'd get between 10 and 12 days of life," he
Meanwhile, in a small corner of Canada, Atlantic Aqua Farms
received a patent in August
for a MAP system designed to keep
shellfish fresh for between 14 and 21 days. The company has
been working on the system for eight years, and while
not the first MAP system
for shellfish, "it is the best,"
"The other MAP system came out of Europe for European
mussels, boosting its shelf life from five to nine days," he
says. "By contrast, our mussels have a 10-to-14-day shelf life
and I can get up to 21 days with our MAP."
The advantage of Fortune's system is its leak-proof
container, allowing customers to throw a tray pack of mussels
in a cart with dry food at a grocery store. In addition, the
MAP mussels can be stored at a normal refrigerated
To date, Atlantic Aqua Farms' MAP system has been endorsed
by the Canadian Food Inspection Agency and the Canadian
"Right now we're doing a study on microbiological challenge,
to prove to the FDA that the packaging is safe for use in the
United States," Fortune says. "The successful outcome of the
challenge will allow us to ship the MAP products into the
United States, which I can do right now, but only using a
time-temperature indicator, which is expensive and unreliable
for case-ready shellfish."
The FDA makes it difficult for processors to use MAP,
concedes Todd Walters, packaging specialist for Koch Packaging
Systems in Kansas City, Mo.
"It's a circus where you have to jump through hoops because
there are so many restrictions," says Walters. "The FDA
monitors the situation closely and as a result, you don't see
many processors using this system
Koch offers a variety of tray-sealing and vacuum chamber
machines that aim to remove the ambient atmosphere from the
package. The company's UltraVac 2100 Dual Chamber Machine is
its most popular, a machine that works best when combined with
Sealed Air's10K OTR bags, says Walters.
"Cryovac's product helps protect against cross contamination
and this system as a whole helps protect the seafood product
from freezer burn," he explains.
The bags have a guaranteed oxygen transmission rate (OTR) of
greater than 10,000 cc per square millimeter per 24 hours. They
don't need a TTI label, because they meet the FDA's OTR
requirements for fresh seafood. Providing a skin-tight,
oxygen-permeable barrier to preserve freshness, the 10K OTR
bags allow the product to be quickly chilled after packaging
with an ice brine solution,
allowing processors to ship
product at the lowest possible fresh temperature and with a
reduced amount of ice. That, in turn, reduces the package
weight and the overall cost of shipping.
The UltraVac 2100 starts at $11,795 and increases in price
depending on the additional features added. For example, it can
be equipped with sealing features, horsepower pump variations
from five to 12 and a digital control panel.
In November 2006, as Wal-Mart was expanding its green
packaging requirements, CPT Plastics in Edgerton, Wis., was
unveiling its Go Green tray, a polypropylene tray produced with
30 percent less energy
"For fresh seafood, we use that in conjunction with a
lidding film that has an oxygen transmission rate of 250,000
cc/m2/24 hours," says Jeff Madrzak, CPT's national accounts
"It goes on the tray, allowing the package to breath and
permitting the equal release and cycling of oxygen in the
package, to create a fresh package with an extended shelf life
of up to eight days," he explains. Essentially, the package
brings fresh oxygen inside and releases the excess carbon
dioxide that, if not monitored or released, will result in the
product souring or in bacterial growth.
CPT has approximately 10 seafood customers using the system
to date, and it works out to be a cost-effective alternative to
MAP, says Madrzak.
"It takes a lot to put a MAP program together and is
expensive with TTI stickers. By contrast, if you use a
breathable film with the correct oxygen transmission rate and
carbon dioxide balance, you don't need to use TTI stickers,"
For processors who already have lidding equipment, the film
installation process is as easy as fitting the equipment to
CPTs tray and film. Obtaining lidding equipment is an expense
that varies according to how many trays per minute
"You can get a machine that will do 10 trays per minute for
about $12,000, and for 30 trays per minute it goes up to
$70,000, depending on the machine," says Madrzak.
The cost of the film works out to between 30 and 35 cents
per package, depending on volume, with the roll calculated to
the individual package size. "Our packaging creates a true,
extended shelf life," he insists.
"How long it lasts depends on the seafood inside, because
some out-gas quicker than others. But we work with each
customer to ensure they are maintaining the right packaging
environment for their particular product."
Seafood processors know all too well that extending a
product's shelf life has to be done safely. With the clock
ticking the moment seafood is harvested, it is essential that
the steps processors take along the way collaborate toward
achieving a fresh, tasty, safe product for
Contributing Editor Lauren Kramer lives in British