170 Chapter 7
tional properties of the powder (Carr et al.
2004 ).Functional Properties
and Applications
The nutritional and functional properties of
casein - based products make them useful
ingredients for a range of products. Milk pro-
teins have always been highly regarded for
their high nutritional value. The caseins and
caseinates, as well as the milk protein con-
centrates, have very good amino acid pro-
fi les, and the milk protein concentrates have
the advantage of being high in bound calcium
(Zwijgers 1992 ). The caseins, caseinates, and
milk protein concentrates also have desirable
fl avor properties — from the relatively bland
caseins to the milky fl avor of the milk protein
concentrates, which can have benefi ts in dif-
ferent applications.
Casein - based products are primarily used
as food ingredients to modify the physical
properties (e.g., water - binding, viscosity) of
the food or to increase its nutritive value.
Consequently, they are often a minor ingredi-
ent in food. However, the type of foods in
which casein - based products can be used is
wide - ranging and includes applications in
vitamin and mineral tablets, instant drinks,
various nutrition foods (dietetic foods, nutri-
tional food bars, sports drinks), pasta, infant
foods, some cereal products, sauces, gravies,
soups, stews, baked products (e.g., bread,
cake products), sweet goods, pastries, cus-Typical Compositions of Milk
Protein Concentrates
Typical compositions of the major compo-
nents of milk protein concentrate powders
are given in Table 7.4. The content of calcium
and phosphorus is higher in the milk protein
concentrate than in skim milk (dry matter
basis). For example, skim milk powder con-
tains 12,500 ppm Ca and 10,000 ppm P,
whereas milk protein concentrates with 80%
crude protein (MPC 80) contain 23,300 ppm
Ca and 14,500 ppm P. However, the contents
of the monovalent ions in skim milk powder
(4,800 ppm Na, 16,500 ppm K and 11,000 ppm
chloride) are higher than those in MPC80
(1,100 ppm Na, 2,400 ppm K and 500 ppm
chloride) (Zwijgers 1992).
There can be variations in the mineral
content of milk protein concentrate powders
with the same content of protein. This is not
only because of compositional differences in
the skim milk, but because differences in
mineral composition also depend on whether
a cold (e.g., 10 ° C; 50 ° F) or hot (e.g., 50 ° C;
122 ° F) ultrafi ltration process is employed
during milk protein concentrate manufacture.
Due to the increased solubility of the calcium
phosphate at low temperature, the retentate
obtained by cold ultrafi ltration is more
depleted in milk minerals than that obtained
by hot fi ltration. Other process modifi cations
can also lead to differences in the composi-
tion of the milk protein concentrate powders,
such as the addition of monovalent salts to
ultrafi ltered concentrate to improve the func-
Table 7.4. Typical composition of milk protein concentrate powders
with 75% and 80% crude protein ( MPC 75 and MPC 80) com-
pared to skim milk powder. Adapted from Anon (1991) , Zwijgers
( 1992 ).
% Component Skim milk
powderMPC 75 MPC 80Protein 36 75 80
Moisture 4.0 5.5 5.0
Ash 7.7 7.5 6.5
Fat 1.0 1.5 2.0
Lactose 51.3 19.5 6.5