vacuum. More recently, steam-only equip-
ment has been designed and is used in beef
processing plants for spot removal. The
steam-vacuum method of pathogen reduc-
tion has resulted in a larger variation of
reduction levels than other moist-heat inter-
ventions tested (Dorsa, 1997). This variation
is attributable to repeated passes of the noz-
zle over the sampled surface of contami-
nated beef having possibly embedded
bacteria, making them more difficult to
remove by steam vacuumization. Plant stud-
ies have demonstrated that a commercial
steam-vacuum system can consistently out-
perform knife trimming for the removal of
bacterial contamination of beef carcasses.
The steam-vacuum system has been
reported to achieve a 5-log cycle (100,000-
fold) reduction ofE. coliO157:H7 on inocu-
lated beef surfaces (Dorsa et al., 1996). Use
of low temperature steam retards the prema-
ture warming of meat and poultry surfaces.
Effectiveness is increased through air
removal prior to treatment with steam since
air otherwise retards the rate at which steam
heats carcass surfaces.
High-pressure pasteurization is accom-
plished through placing meat cuts in a water
column where additional water is headed to
the column resulting in a high pressure. The
high pressure and subsequent release results
in the disruption of bacteria.
Irradiationmay be referred to as cold pres-
surization if treatment by radiation is noted.
This is an effective method of reducing bac-
teria and can effectively eliminate them at a
high dosage.
The effects of cetylpyridinium chloride
(CPC) on the inhibition and reduction of
Salmonellahave been demonstrated success-
fully as a pathogen intervention technique
for poultry carcasses. This compound has
been used safely for over 30 years as an oral
hygiene product. CPC is effective in prevent-
ing bacterial attachment and the reduction
of cross-contamination. Treatment with
CPC does not affect the physical appearance
of poultry products.Electrical stimulationis
another potential means of microbial load
reduction on the surface of carcasses.
Activated lactoferrin (ALF) is a natural
and novel antimicrobial compound that was
first approved by the USDA for use on fresh
beef in January 2002. Later, additional
approval for ALF was granted for designa-
tion as a “processing aid” for carcass rinse
treatments. Thus, this compound may be
used to treat carcasses without a label decla-
ration. The currently approved use of this
carcass treatment involves a patented formu-
lation of lactoferrin that is electrostatically
applied, followed by a water rinse. This treat-
ment physically removes bacterial contami-
nants from carcass surfaces, especially E. coli
0157:H7,L. monocytogenes, and Salmonella
spp. The growth of at least 30 species of bac-
teria may be retarded by ALF.
The commercial form of ALF is derived
from skim milk or whey. Furthermore, the
FDA has classified this compound has a
GRAS substance. When lactoferrin is iso-
lated from milk, it becomes susceptible to
molecular alterations resulting from pH
change, heat, proteolysis, or ionic balance.
Any of these conditions can diminish
antimicrobial effectiveness. “Activated”
lactoferrin is the result of patented technol-
ogy that provides a stabilized form of lacto-
ferrin retaining the desired antimicrobial
properties.
The ability of ALF to bind firmly to bac-
terial cells results in blocking the attachment
of bacteria to surfaces such as beef tissues.
The physical attachment of bacterial cells,
especially E. coliO157:H7, to carcass sur-
faces complicates removal and contributes to
proliferation and growth of bacteria during
subsequent storage. ALF can bind to tissue
components such as collagen that provide
anchor sites for bacterial attachment on car-