Handbook of Meat Processing

Quality Assurance 557

relative humidity, as well as the intended and

measured weight loss, should be specifi ed

and recorded.

Bacon

Bacon differs from other raw cured meats in

many aspects:

• Other cuts are used for curing (e.g., whole
  pork sides or bellies rather than ham).


• Curing is by brine injection.


• Maturing lasts only a few days.


• The product is sometimes heat - treated (hot
  smoked) after curing and almost always
  cooked before consumption.
  For details, see earlier chapters of this
  volume. For the quality and safety of the
  product, the quality of the raw material (espe-
  cially the fat quality), the composition of the
  curing brine, the proper maintenance of the
  multineedle injectors (to ascertain even dis-
  tribution of the brine and to avoid introduc-
  tion of physical hazards), and the times and
  temperatures during curing and further pro-
  cessing are essential.

Quality Assurance during

Packaging, Storage, Distribution

The climate in the slicing and packaging

room should be adjusted so as to avoid mois-

ture condensation and the undesired surface

growth of microorganisms. As a rule, the

relative humidity in the slicing and packag-

ing room should be below 60%. The tem-

perature depends on the type of product and

the time the product is held in the packaging

room. To avoid contamination of the product

by psychrotrophic spoilage bacteria and by

listeriae, hygienic design of the slicing and

packaging machinery is essential, and an

appropriate cleaning and disinfection plan for

it should be in place.

To prevent mold growth and to delay oxi-

dative deterioration, the residual oxygen

level in the package should be kept below 1%

slaughtering and butchering hygiene, but it
cannot be completely ruled out. Hence, the
need for salting and salt equilibration; these
processes must be carried out at 5 ° C or below
and continued until the target water activity
of 0.96 is reached in all parts of the ham.
The levels of salt must be specifi ed and
carefully controlled, in order to inhibit growth
of undesired microorganisms while avoiding
over - salting, especially of the surface layers.
The same applies to the levels of curing
agents (nitrite, nitrate) in the salt, which
should be high enough for the desired sensory
properties but low enough to comply with the
maximum residual levels specifi ed by offi cial
regulations. Appropriate work instructions
should specify the composition of the salt (in
particular, the levels of nitrite and/or nitrate
in the salt), the salt content of the brine (if
applicable), the amount of salt and/or brine
to be added per kg of meat, the size of the
cut (maximum distance from the surface to
the geometric center), the temperature
( ≤ 5 ° C), and the minimal time for salting and
salt equilibration. Records should include
weighing and time - temperature protocols.
Also, the results of visual inspections and/or
measurements of the fi nal salt content or a w
value in the core should be recorded, because
the salt diffusion rate may vary between indi-
vidual cuts.
After salting and salt equilibration, it is
important to avoid undesired changes at the
surface of the hams. For quality and safety of
the product, extensive washing should be
avoided, and the surface should be dried at
low temperatures. Smoking should be con-
trolled as in the production of fermented sau-
sages (see above).
In particular, Mediterranean - type raw
hams are usually subjected to extensive
aging, to leave enough time for enzymatic
processes, which makes the hams tender and
tasty. Aging normally takes place at tempera-
tures above 15 ° C. The hams are stable at
ambient temperatures if the water activity is
below 0.90. Aging time, temperature, and