274 Chapter 11
Openness in texture due to gassiness may
be ascribed to coliforms if it manifests during
the early stages of ripening. However, late
blowing during ripening is generally due to
gas production by Clostridia. In addition,
starters may contain gas - producing culture.
Cheese - making conditions leading to exces-
sive lactose in the curd lead to gas production
by yeasts and other microorganisms. Proper
acid development, moisture control, and
desirable salt levels are the factors necessary
for suppressing gas producers in cheese.
Flavor Issues: The nature and intensity of
fl avor are considered to be critical factors in
consumer acceptability. In addition, manu-
facturers of process cheese are concerned
with the fl avor, body, and texture of various
lots of natural cheese, which are graded on
fl avor, body, and texture so that after blend-
ing, the desired characteristics are built into
the fi nished process cheese. To maximize
market acceptability and economic returns,
cheese manufacturing operations engaged in
natural cheese varieties must maintain
optimum fl avor quality. Manufacturing vari-
ables usually controllable by a cheese maker
contribute signifi cantly to fl uctuations in the
quality of cheese fl avor. Table 11.4 lists
fl avor defects, causes, and actions to correct
the problems.
Freshly pressed cheese displays little or
no typical fl avor commonly associated with
cheddar or colby cheeses. Presence of non -
typical fl avors at this point indicate quality
issues with cheese milk, starter inactivity, or
contamination, and probable inconsistencies
in the cheese process. Strictly following stan-
dard procedures to achieve a consistent rate
of acid development, cooking temperature
and time, curd matting technique, and salting
regimes ensures minimal variation in cheese
fl avor quality.
A reasonable constant retention of mois-
ture, fat, casein, and minerals in cheese
curd should ensure a uniform fermentation
medium for ripening organisms. Moisture
control factors include:Frequently, defects in color, body, and
texture are concomitantly noticed with fl avor
problems in cheese. In this regard, open
texture or holes in cheese may pose problems
ranging from minor to serious. These holes
may be mechanical or biological in origin.
The size, appearance, and shape of the hole
may give a clue to the problem. Mechanical
holes are recognized by their irregular size
and angular shape, and they have a dull
appearance. This defect arises from improper
knitting of curd during pressing. It can be
traced back to unfavorable conditions during
acid production, cooking, matting, greasy
curd surface resulting from improper tem-
perature, undissolved salt, and inadequate
pressing procedure. Because this defect is
basically mechanical in nature, no fl avor
problems are associated with it. Consequently,
it is not considered as a serious defect.
Open texture of biological origin may be
classifi ed as follows:
- Fish eyes, ascribed to yeast fermentation,
are characterized by a round, glossy, and
gas - induced open texture. Excessive gas
generation by yeast growth leads to spongy
or honeycomb - like body, eventually fl at-
tening to give long narrow slits. - Small pinholes are identifi ed as being fairly
uniform and in large numbers. They are
derived from the production of gas as a
result of undesirable bacteria - like coli-
forms within the cheese body. Extensive
growth of the bacteria (1 million CFU/g)
causes a spongy or bloated condition with
an accompanying fruity fl avor defect. - Large, uniformly distributed gas holes
resemble Swiss cheese eyes. If the holes
are caused by the growth of Propionibac-
terium shermanii , a defi nite sweet and nut -
like fl avor accompanies the appearance of
such holes. - Slit or fi ssure formation is recognized by a
narrow and long cut in the cheese. It is also
microbial in origin in that gas formation pre-
vents complete welding of curd surfaces.