Food Safety Magazine - June/July 2013

SANITATION
floors and knife racks) to FCS, and from
FCS (cutting boards and preparation
sinks) to product. According to a report
by the 2004–2006 Conference for Food
Protection L. monocytogenes Intervention
Committee, 18 sanitation programs to
specifically address L. monocytogenes consist
of three actions: 1) effective removal
of soil; 2) an effective rinse step and 3)
proper application of a sanitizing agent,
which includes contact time, concentration
and temperature. A sanitation
program should also implement written
procedures for proper cleaning and sanitizing
FCS and non-FCS. These procedures
should include the frequency of
cleaning, chemicals to use, instruction
on how to perform the task and the
steps to verify it is being done correctly.
A visual examination of all FCS should
be done before the start of operations
to ensure compliance with cleaning procedures
and to take corrective action if
necessary. Written procedures for food
establishments should include the cleaning
and sanitizing of maintenance tools.
Every food establishment must have a
method for verifying the effectiveness of
its cleaning and sanitation program. The
effectiveness of sanitation programs can
be verified in different ways, and often a
combination of approaches can be used.
When determining which method to
use, consider factors such as:
• How difficult the area is to clean
• Whether possible L. monocytogenes
harborage sites are present
• Whether there have been previous
problems with sanitation
The person in charge should be responsible
for ensuring that employees
are properly trained for the tasks assigned
to them and that they fully understand
how to perform the sanitation
procedures. This includes mixing and
testing cleaning and sanitation solutions
for proper strength, cleaning and sanitizing
certain equipment according to a
prescribed schedule and checking to be
sure equipment and surfaces are cleaned
as needed throughout the day. Some of
the methods that can be used to verify
the effectiveness of sanitation programs
include:
• Observation and monitoring
• Rapid sanitation tests
• Microbiological testing
These methods vary by cost and level
of technical expertise needed to use
them.
The sanitation and overall control
programs will be determined by whether
the final product allows growth of L.
monocytogenes. Because
of the diversity of RTE
foods being produced,
the processes used
and the prevention
and control strategies,
companies need to
have challenge tests
done on their RTE
food products if there
is uncertainty that L.
monocytogenes may or
may not grow during
the shelf life of the
product. 19
Biofilms
One of the big concerns
for processors is
biofilm formation. Persistent
strains may not
be better than transient
strains for biofilm formation,
but they seem
to resuscitate faster than non-persistent
ones after treatment. 20 Biofilms are generally
resistant to standard cleaning and
disinfecting systems. One suggestion is
to scour them off FCS with scallop shell
powder. 21 However, most plants use sanitizers
exclusively, and while there are
many available for cleaning equipment,
not all are equally effective against L.
monocytogenes biofilms, and the results
of experiments do not always agree with
each other. In one study of 21 commercial
sanitizers tested, 22 peroxyacetic acid
(PAA), chlorine dioxide and acidified
sodium chlorite-based products gave
the best decrease (5 log 10
). In another
study, 23 biofilms formed at 20 °C were
more resistant to PAA than biofilms
formed at 5 °C. The most effective
sanitizer on contaminated stainless steel
coupons was quaternary ammonium
“All countries should
consider making
listeriosis a notifiable
disease and have in
place both active and
passive surveillance
systems for noninvasive
gastrointestinal
infections.”
compound followed by PAA and chlorine.
Low concentrations of ethylenediamine
tetraacetic acid affect biofilm
formation by inhibiting its initial adherence.
Complete pathogen inactivation
was obtained with a treatment of chlorine
dioxide gas for 30 minutes against
biofilms on slicers and peelers in a third
study. 24 However, in a fourth study, 25 no
sanitizer caused more
than a 1.5-log CFU/
cm 2 reduction of
Listeria when treated
and untreated stainless
steel or aluminum
coupons that had
been cut from a used
deli meat slicer were
compared. Additionally,
no cleaning clothcontaining
sanitizer
produced more than a
1-log reduction compared
with controls. It
may be good to rotate
sanitizers for various
applications, including
boot-dip stations
for reentry into RTE
areas.
Novel Interventions
A variety of natural
GRAS (generally recognized as safe)-
approved chemicals have been tested on
different RTE products for their antilisterial
properties without any product
quality deterioration. These include
essential oils, cinnamon powder, apple
skin extract and organic acids like ferulic
and malic acids. In addition, EO water,
intense pulsed light (IPL), combinations
of ultraviolet (UV) and hydrogen peroxide,
nisin and heat, and flash pasteurization
with lauryl arginate ester have been
shown to be effective hurdles. Ultrahigh
pressure (UHP), IPL and pulsed electric
field (PEF) are emerging processing
technologies developed to enhance the
safety while maintaining the fresh-like
quality of food. However, UV light is
not as effective as other treatments in
destroying L. monocytogenes. Decontamination
methods using gamma radiation,
32 F o o d S a f e t y M a g a z i n e