1. L1N25P118 www.professionalpasta.it profpast@tin.it
28
The world of pasta
offers a wide variety of
products that are the
fruit of Italian creativ-
ity. Among the various
types, filled pastas are
produced with hard
wheat semolina and
sometimes other ingre-
dients including soft
wheat flour, egg, vege-
tables (spinach, tomato,
etc.) and are then filled
with other raw materi-
als such as meat, vege-
tables, cheese, egg and
fish. Pasta types stuffed
withmeatmaybedried
- prepared exclusively
using semolina or
refined durum wheat
andwater-orfreshand
stabilized.
The purpose of this
article is to explain the
microbiological char-
acteristics of meat and
some meat products
such as Parma ham
and speck which,
among the various
types of fillings, are the
ingredients preferred
by many consumers.
As a food, meat is
highly perishable
because it provides a
good base for the
proliferationofvarious
types of microbes
whose development is
tied to certain alter-
ations (change in color
and unpleasant odor).
These alterations are
potentially capable of
compromising the
edibility of the product
with ensuing reper-
cussions on the level of
health and hygiene
that affect, above all,
the health of the
consumer, but also
entail economic conse-
quences for the pasta
maker because not
only is the shelf-life of
the product reduced,
but the product itself
may no longer conform
to the health and
hygiene standards
and, as a result, must
be disposed of.
Factors influencing
meat shelf-life
The limited shelf-life of
fresh meat is influ-
enced by a series of
interrelated factors that
have a technological
significance given that
when these factors are
taken into consider-
ation, alteration in the
meat can be avoided.
Of extreme importance
are the temperature
and relative humidity
of the storage environ-
ment. For example,
meat stored at +3°C
remains unchanged for
several days, a signifi-
cantly greater period of
time than if it is kept at
room temperature (in
this case, its character-
istics would remain
unchanged for approx.
24 hours). In terms of
humidity levels over
80% increase the risk of
development of surface
mold on meat-based
products.
Meat should be kept
out of the light since
this triggers lipo-oxida-
tion of the fatty tissue
that could cause the fat
to go rancid. Another
factor to be taken into
MICROBIOLOGICAL CHARACTERISTICS OF MEAT FOR FILLINGS
INDICATIONS TO PREVENT
PRODUCT LOSS AND INCREASE SHELF-LIFE
by Francesca Bonifacio

2. consideration is oxygen
in the atmosphere
which may be utilized
to find effective preser-
vation techniques that
make use of vacuum or
modified atmosphere
packaging.
Last but not least, it
should be remembered
that microbiological
flora are present to a
greaterorlesserdegree.
Origins of microflora
in meat
The microflora that
can be isolated in the
various types of meat
flesh used in fillings
include:
Πintrinsic or endoge-
nous microflora,
so-defined because
they are comprised
of microorganisms
present in the living
animal; generally
these microorgan-
isms originate in
the intestine and
are an indication of
the state of health
of the animal at the
time it is slaugh-
tered;
Πextrinsic or exoge-
nous microflora
that derive from the
environment in
which the various
handling phases of
the side of meat
(during butchering
and distribution)
take place, and
from the operator
involved.
The surface microbic
level is a good indica-
tion of hygienic condi-
tions during produc-
tion phases: the less
attention paid to
hygienic standards, the
higherthelevelwillbe.
Microbic groups
The main microbic
groups found in fresh
meat following butch-
eringarethefollowing:
Πbacteria: the most
common are sapro-
phyte bacteria(1) or
ubiquitous alterants,
given that they are
normally present in
the soil, water or air
29
L1N25P118 www.professionalpasta.it profpast@tin.it

3. and their excessive presence
causes a decline in the
organoleptic characteristics
of refrigerated meat.
Included in this group are
those bacteria belonging to
Micrococcus, Pseudomonas,
Enterobacteria, Aeromonas,
Alteromonas, Acinetobacter,
Flavobacterium and Clostridium,
of which some are
psychotrophs, i.e., capable of
developing even at tempera-
tures less than +4 °C. Meat
may also be contaminated
by potentially pathogenic
bacteria such as Salmonella,
Bacillus, Enterotoxic staphylo-
coccus, Clostridium botulinum,
Clostridium perfrigens, Yersinia
enterocolitica, Campylobacter
and Listeria monocytogenes;
Πeumycetes: yeasts and
molds are part of this group.
The types of yeasts normally
found on the surface of
meat are Saccharomyces,
Debaryomyces, Candida,
Rhodotorula,Cryptococcusand
Pichia, while Aspergillus,
Geotrichum, Penicillium,
Mucor, Alyternaria and
Cladosporium are the types of
molds. Eumycetes are also
capable of causing alteration
and decrease in organoleptic
characteristics. It should also
be taken into account that
molds can also grow at low
temperatures. It is not
unusual to find molding on
frozen meat at temperatures
of just above –15 °C.
Factors in microbic development
The penetration of microor-
ganisms in large pieces of
unprocessed meat is blocked
by a number of barriers
(consisting of cell walls,
connective tissue, covering fat)
30
L1N25P118 www.professionalpasta.it profpast@tin.it

4. that must be broken through in
order for the microorganisms
to get at the nutrients required
for their growth. Therefore,
although meat possesses the
elements that meet the nutri-
tional and energy require-
ments of wide-ranging and
h e t e r o g e n e o u s
microbic groups, it
does not represent
an easy terrain for
colonization.
Two other factors
to be considered
regarding the
microbic develop-
ment are water
activity and pH.
Water activity values of 0.98
and 0.99 (which indicate the
amount of free water available
in the host in which the
microflora are found) are
generally measured in the
meat, thus contributing to the
creation of a favorable environ-
ment for the development of
numerous microbic species. In
terms of pH, following the
death of the animal, values of
5.5 and 5.7 are reached. As the
pH level drops, a slow-down in
the rate of growth is observed
and the first to be inhibited are
bacteria followed by yeasts and
molds.
Parma Ham and speck:
microbiological aspects
As an example of meat prod-
ucts used in the production of
filled pasta, we will take a brief
look at Parma ham and speck.
The process of producing
Parma ham calls for the use of
anatomically whole pieces and,
assuming that the animals
utilized are healthy, this should
guarantee the absence of
microorganisms. However,
during aging or following
de-boning, some microbiologic
alteration could occur attribut-
able to environmental contami-
nation or fecal contamination
spread through blood vessels.
The microorganisms generally
present in preponderance are
clostrides and, in particular, C.
perfrigens (aided in their devel-
opment by the absence of
nitrites). These cause the prod-
uct to swell up and trigger
putrefactive processes that
cause irreparable deterioration
in quality. Other alterations,
known as shank defect, vein
defect, under-bone defect and
joint defect, are caused by the
enterobacteria that proliferate
in those areas in which curing
was not performed properly
and the salt was unable to
penetrate fully. In addition,
molds can also encounter colo-
nization conditions on surface
layers.
For speck, correct salting and
smoking should guarantee the
absence of microbic alterations.
However, in the final phase of
aging, molds of the Penicillium
and Aspergillus type may be
found that are capable of
getting past the inhibiting effect
of smoking. Potentially toxic
funginspeciessuchasA.glacum,
A. flavus and A. ochraceus have
also been isolated.
Probable points of
contamination and preventive
measures to be adopted
During the production of filled
pasta, there are a number of
phases that should be moni-
tored to avoid undesiderable
loss of product quality. Among
the various phases that charac-
terize the pasta-making
process, this article identifies
those points in which there is
greater probability of microbic
contamination and how to
avoid its development in order
toguardagainsteconomicloss.
Delivery of raw materials
When purchasing meat prod-
ucts, the professionalism of the
supplier must be evaluated in
order to prevent contaminated
foods entering the company.
When delivery is made,
supplier certification docu-
ments must be checked, the
shipment and truck inspected
31
L1N25P118 www.professionalpasta.it profpast@tin.it

5. and it should be verified that
the correct temperature was
adopted and maintained.
If supplier certification docu-
ments are not included, the
shipment should be refused
and acceptance suspended
until certification is supplied.
Cold storage
For proper preservation, there
must be suitable and separate
refrigerators for the various
raw materials.
It is also necessary to define a
standard storage method and
correct rotation of the stocks on
the basis of time/temperature,
verifying the storage times and
temperatures.
Necessary preventive measures
include proper maintenance
and setting of the temperature
monitoring system, program-
ming of sanification procedures
through weekly inspection of
the refrigeration cells and stor-
age areas and informational and
training operations with written
operating instructions for
employees involved in ware-
housing and sanification.
On a daily basis, storage temper-
ature and duration must be
checked and the temperature
corrected if necessary.
Raw materials must be checked
and it must be decided how they
are to be used. Raw meat must
be preserved in such a way that
liquid does not leak out from it
and contaminate other food-
stuffs. Different varieties must
never be preserved in the same
packaging and raw meat must
be placed in the refrigerator or
frozen as quickly as possible.
Cutting
Chopping or cutting up of meat
must be performed on separate
surfaces. Knives and cutting
boards must be thoroughly
washed with soap and hot
water after each use.
Cooking
For the meat to be cooked prop-
erly, it must be cut into smaller
pieces to insure that the cook-
ing temperature reaches the
center of the piece of meat in
order to effectively reduce the
microbic level. In fact, the
proper combination of cooking
temperatures and times can
eliminate microbes.
Cooling
To avoid microbic proliferation
if the product is not rendered
sterilethroughcooking,follow-
ing cooking the food must be
cooled quickly and refrigerated
at a temperature of approx.
3-4°C.
Forming unit
In the forming unit, vegetative
forms may collect that can be
preventedthroughprogrammed
sanification using proper plans
and procedures and training of
personnel. It is recommended
that a microbiologic check of
internal surfaces be performed
before production start-up. If
standard limits are exceeded,
personnel should be informed
of the issues involved and the
sanification program revised.
If, when a visual check is made,
there is residue or build-up
from previous production, the
system must be cleaned.
Pre-dryer and cooling
During this phase, monitoring
of the treatment temperature
and times is extremely impor-
tant for the maintenance and
setting of the monitoring
system of these two factors. The
risk that could arise involves
the presence of bacterial
spores, vegetative forms and
molds. In particular, it is the
bacterial spores (in some cases
heat-resistant) that are not
eliminated and with inade-
32
L1N25P118 www.professionalpasta.it profpast@tin.it

6. quate product cooling, they
may find the conditions in
which to germinate. Standard
conditions must be restored
when given limits are exceeded
and the product examined and
handling procedures reviewed
if the results do not conform.
Packager and gas dosage
Once again in this production
phase, vegetative forms, bacte-
rial spores and molds may be
present. Therefore, it is recom-
mended that preventive and
programmed maintenance
standards for the system be set,
together with personnel train-
ing standards, and that written
operating instruction be
provided for those assigned to
packaging.
In this phase, the analyses
performed on the product
samples include proper seal-
ing, water activity, moisture
levels, residual oxygen and gas
blend. Microbiologic tests are
performed on the finished
product for overall bacterial
count and detection of Staphy-
lococcus, Salmonella, C. perfrigens,
molds, Listeria, Escherichia coli,
Bacilluscereusandenterobacteria.
Corrective actions include
extraordinary maintenance,
restoration of standard operat-
ing conditions, examination and
handling of non-conforming
product and, if required, revi-
sion of HACCP procedures.
Remember that for those
production processes which
require double pasteurization,
samples for testing should be
taken following the cooling
and not the pasteurization
phase.
Storage areas and transport
Once again in this phase,
proper maintenance and
setting of the temperature
monitoring system is impor-
tant. If the temperature is
above the standard tempera-
ture, the original value must be
reset and the product exam-
ined to verify that it conforms
or determine if it has under-
gone qualitative changes from
either a health and hygiene or
organoleptic standpoint.
Finally, as for all alimentary
products, health/hygiene stan-
dards must be respected
during production, packaging
and preservation. To obtain a
good product, it is indispens-
able to start with good quality
raw materials with low microbic
count. In fact, microbic pres-
ence has an influence on the
product, altering its flavor,
odor and color.
If the fresh pasta is produced in
small workshops in which
treatment to reduce the
microbic count is not provided
for, it should be remembered
that microbic development is
fostered by the moisture level
and, above all, poor cooling
processes.
NOTES
(1) Saprophyte: an organism that
lives on decomposing organic
substances.
33
L1N25P118 www.professionalpasta.it profpast@tin.it