252 Chapter 10
points. It also is important for cheese output
in a cheese plant.Moisture Control
The U.S. Food and Drug Administration
(FDA) regulations require a minimum of
39% moisture in cheddar cheese. Theoretically,
an increase of 2% moisture in cheddar cheese
from 36% to 38% can lead to signifi cantly
more output, as shown below.
Assuming 75% retention of milk protein,
93% retention of fat, 30% retention of lactose,
and 35% retention of minerals in cheese,
cheese will have dry matter as follows:Protein=×=075 32 240...lbs 1...
Fat=×=0 93 3 6 3 35lbs...2...
Lactose=×=0 30 4 7 0 14lbs...3...
Minerals=×=0 35 0 8 0 28lbs...4...
Adding lines 1 through 4, the dry matter
yield is 6.17 lbs.
Assuming 36% moisture in cheese and
1.55% salt absorbed by cheese curd:
The cheese yield
dry matter weight
moisture=×
−−
100
100
()/
( % % salt)
./( .)
./. .%.=× −−
=× =
100 6 17 100 36 1 5
100 617 625 987
In another scenario, assume the moisture
level in cheese is 38%. Then:
The cheese yield
dry matter in cheese)/
moistur=×
−
100
100
(
(% e− salt
=× −−
=× =%)
./( .)
./. .%
100 6 17 100 38 1 5
100 6 17 60 5 10 20
In this illustration, in a cheese operation
processing 500,000 lbs of milk per day, there
is an opportunity to generate an extra 1,650 lbs
of cheese on a daily basis by tightening the
moisture in cheese from 36% to 38%.Factors for Optimizing Cheese Yield
Cheese yield is defi ned as pounds of cheese
obtained from 100 pounds of milk. It depends
on the milk and cheese composition, as well
as the added salt level. Generally, to achieve
high yields of cheese, milk with high levels
of casein and fat are selected. Milk should be
of excellent microbiological quality. Milk
with high bacteria counts usually displays
enzymatic breakdown of protein, thereby
reducing casein content leading to poor
cheese yield. In addition to milk quality, pro-
cessing parameters affect the yield of cheese.
Attention should be focused on the coagulum
cutting procedure, heating rate during cook-
ing, timing of salting after milling, tempera-
ture during pressing, washing of curd, and
the heating and stretching step in mozzarella
cheese.
The cheese - making process partitions
major constituents of cow ’ s milk into cheese
and whey. For example, in cheddar cheese,
approximately 4% of the water, 93% fat, 75%
protein (96% casein, 7% whey protein), 35%
minerals, and 3% of the lactose of the milk
are retained. On the other hand, approxi-
mately, 96% of the water, 7% milk fat, 25%
protein (4% casein, 93% whey protein), 65%
minerals, and 97% of the lactose of the milk
end up in whey.
Figure 10.5 illustrates a mass balance
diagram for cheddar cheese. For cost control,
it is useful to monitor incoming milk, cheese,
and whey fractions for fat, protein, mineral,
and moisture percentages. This can assist in
auditing the plant ’ s performance with respect
to typical retention values. It is advisable to
develop the data relevant to a specifi c cheese
operation in relation to cheese varieties
during the course of a year. Undue loss of fat
and protein in whey should be investigated
as a managerial tool. The quality of cheese
must be maintained while steps are taken to
optimize the yield of cheese.
Controlling moisture and fat in cheese is
necessary from legal, cost, and quality stand-