256 Chapter 13
dation in beef, leading to the enhanced
display life of the meat. Additionally, Camo
et al. (2008) investigated and compared the
effect of two natural antioxidant sources
(rosemary and oregano extracts) incorpo-
rated into an active package fi lled with a
modifi ed atmosphere on the display life of
lamb steaks. These workers found that a rose-
mary extract, a rosemary active fi lm, or an
oregano active fi lm resulted in enhanced oxi-
dative stability of lamb steaks. Also, active
fi lms with oregano were signifi cantly more
effi cient than those with rosemary, exerting
an effect similar to that of the direct addition
of the rosemary extract and extended fresh
odor and color from 8 to 13 days compared
to the control.
Active packaging has the advantage of
maintaining the preservative effects of
various compounds (antimicrobial, antifun-
gal, or antioxidant), but without being in
direct contact with the food product. This is
an important development, considering the
consumer drive toward clean labeling of food
products and the desire to limit the use of
food additives.Summary and Future Trends in
Meat Packaging
In recent years, much attention has focused
on the shift from consumers buying meat at
the family butcher shop to purchasing it at
the local supermarket. More and more tradi-
tional butcher shops have closed because
they cannot compete on price, offer the same
supermarket one - stop shop opportunity, or
provide the extended shelf life of MAP meats
to the consumer that are available on refriger-
ated supermarket shelves. This is the situa-
tion in most developed countries, particularly
within the EU, where sales of fresh meat
have increased in supermarkets at the expense
of the specialized butcher ’ s store (Mannion
1995 ). However, recently, consumers have
become very much more discerning with
respect to the origins of the food theypolyethylene (LDPE) and high - density poly-
ethylene (HDPE) fi lms has been studied in
food systems. In such systems, release rates
and migration amounts must be closely mon-
itored for the system to effectively preserve
the contents of the package (Han 2000 ).
Looking to the consumers ’ demand for
chemical preservative - free foods, food man-
ufacturers are now using naturally occurring
antimicrobials to sterilize and/or extend
the shelf life of foods (Han 2005 ). Present
plans envisage the possible use of naturally
derived AM agents in packaging systems for
a variety of processed meats, cheeses, and
other foods, especially those with relatively
smooth product surfaces that come in contact
with the inner surface of the package. This
solution is becoming increasingly important,
as it represents a perceived lower risk to the
consumer (Nicholson 1998 ). Various bacte-
riocins, such as nicin, pediocin, lacticin, pro-
pionicin, etc., can be incorporated into foods
and/or food packaging systems to inhibit
growth of spoilage and pathogenic microor-
ganisms (Daeschul 1989 ). The extracted
bacteriocins, which are generally small
molecular weight peptides, can be utilized in
various ways; however, it is very important
to characterize their resistance to thermal
treatment and pH (Han 2005 ). The storage
temperature may also affect the activity of
AM packages. Several researchers have
found that the protective action of AM fi lms
deteriorated at higher temperatures, due to
high diffusion rates in the polymer (Vojdani
and Torres 1989 ). The diffusion rate of the
AM agent and its concentration in the fi lm
must be suffi cient to remain effective
throughout the shelf life of the product
(Cooksey 2000 ).
Antioxidant packaging is a recent devel-
opment in active packaging technologies that
has had some success. Ner í n et al. (2006)
described the promising results of a new anti-
oxidant active packaging system; a plastic
fi lm with an embodied rosemary extract was
able to inhibit both myoglobin and lipid oxi-