246 Chapter 10
The quality of salt used in cheese plant
must conform to the specifi cations defi ned in
an industrial standard publication similar to
Food Chemicals Codex. It should be free of
additives, pathogenic microorganisms (staph-
ylococci, salmonella, coliforms), and envi-
ronmental pollutants. The suggested particle
size should range from 20 to 70 mesh. The
typical total bacterial count should not exceed
1,000 CFU/g, and the yeast and mold count
should not exceed 100 CFU/g. Extraneous
matter measured by the USDA sediment test
should not exceed 1.5 mg (No. 2 pad), using
a 250 - g sample of salt. To avoid moisture
absorption and caking, the salt should be
stored in sealed, plastic - lined bags under
rodent - proof conditions.
Factors to be considered for ensuring pre-
cision and uniformity of salt incorporation
are discussed below in relation to the salting
method.Dry Salting
Dry salting milled curd establishes quick dis-
tribution of the salt, whereas rubbing of salt
on cheese surface appreciably delays the
equilibrium conditions. The amount of salt
added to cheese curd is determined by the
weight of curd, the desired salt level in
the cheese, and the size of the curd particles.
The salt penetration is accelerated by lower
pH and higher moisture content of curd, but
is slowed by larger curd size and delays
salting of milled curd.
For a given variety of cheese, the yield
of curd may be considered relatively con-
stant. Accordingly, the amount of salt added
to the curd varies with the quality of the
curd after milling. In general, 2.5 + / - 0.5 lbs
of salt/1,000 lbs of milk is used in cheddar
and American cheese making. Approximately
60% of the added salt is retained in the
cheese. Assuming 95 pounds of cheese curd
obtained from 1,000 pounds of milk, this
level corresponds to 1.3% to 1.9% in cheese.the role of salt in cheese manufacture. Salting
may be accomplished by adding crystalline
salt to the curd prior to pressing, as in cheddar,
colby, and Monterrey Jack cheese varieties.
Another technique of salt incorporation
involves immersion of pressed cheese blocks,
wheels, or discs in a cold brine solution con-
taining approximately 23% sodium chloride.
Coarse salt is rubbed on the surface of certain
cheese varieties. In each case, the contact
time of the salt with the cheese curd is
designed to permit adequate diffusion of the
salt into the interior of the cheese bulk.
Cheeses that are salted in brine include
Gouda, Edam, Swiss, camembert, Brie, moz-
zarella, parmesan, Romano, provolone, and
blue - veined varieties. In rare cases, both dry
salting and immersion in brine may be prac-
ticed. In mechanized cheese making, brine
solution is injected into the cheese curd.
Most cheese varieties contain 1.2% to 2%
salt. For cheddar cheese containing 38%
moisture and 1.2% salt, the effective salt
level would amount to 3.2% salt in the
aqueous phase. Similarly, in mozzarella con-
taining 50% moisture and 1.2% salt, the
effective level of salt would be 2.4%. For
pickled cheese, such as feta, much higher
levels of salt are used. The concentration of
salt in cheese curd and the manner of its
incorporation play an important role in the
characteristic cheese fl avor and texture
development.
The function of salting is three - fold. First,
it imparts to cheese an agreeable taste.
Second, it directs the fermentation pattern of
the cheese ripening process by selectively
inhibiting undesirable microorganisms and
controlling the growth rate of ripening organ-
isms. Third, the salting process results in
syneresis and removal of additional whey
from the cheese curd to impart typical tex-
tural quality to cheddar cheese. The regula-
tion of moisture in cheese subsequently
affects the fermentation process, leading to
specifi c fl avor production in cheese.