Dry Milk Ingredients 153components can interact with other ingredi-
ents when formulated and processed into a
fi nal recombined dairy product or food
product. For the purpose of quality control,
it is benefi cial for milk powder suppliers to
work with end users of their ingredients and
understand how their products will be formu-
lated and processed. This allows the develop-
ment of more appropriate fi tness - for - purpose
specifi cations and methods for testing the
attributes of milk powder ingredients.
Milk powders can also impact fl avor and
color of products. Buttermilk is sometimes
used as a partial replacer of other milk
powders to improve the fl avor of dairy prod-
ucts. In some applications, a bland milk
powder is desirable so as not to impart fl avor
tones which may be undesirable for the spe-
cifi c product.Recombined and Reconstituted
Dairy Products
Early reconstitution and recombination was
for the manufacture of simple products such
as liquid milk, sweetened condensed milk,
and evaporated milk. Today all traditional
milk products can be made from milk powder
and milk - based ingredients. Figure 6.4 shows
the operations involved in the process
required for the production of recombined
milk.
Reconstitution is simply the mixing
of milk powder with water. For example,
reconstituted skim milk and reconstitutedous phase to a water - in - oil emulsion with oil
as the continuous phase. A typical example
of this method is that by Vuillemard et al.
(1990).
The foaming and emulsifying properties
of milk powders can be infl uenced by their
composition and processing treatments
applied to the milk as well as the conditions
used for the formation of emulsions and
foams. Physical changes can be made to the
powder morphology to enhance the foaming
capacity. This may be done by manufacture
of high occluded air in powders by altering
processing variables or by injecting air into
the concentrate prior to drying.
Storage Stability of Milk Powders
The physical properties of milk powders may
be altered when they are stored. Storing
powders at high temperature and humidity
accelerates the damage to milk powders. A
number of phenomena and reactions cause
the quality of milk powders to deteriorate,
including lactose crystallization chemical
and enzymic reactions. The consequences of
these reactions are a loss of solubility and
impairment in many of the other physical
(e.g., increased tendency to cake and reduced
fl owability) and functional attributes (e.g.,
gelling, emulsifying, and foaming) of milk
powders. The effects of aging on the proper-
ties of milk powders have been reviewed
(Thomas et al., 2004 ).
Applications of Milk Powders
Milk powders are used in a range of applica-
tions. The physical functional attributes of
powders govern their ability to contribute to
attributes of the fi nal product. Figure 6.3
depicts the road map for using milk powders.
Success in using milk powders requires an
understanding of the properties of the indi-
vidual powder ingredients and how their
functionality is expressed in the fi nal food
product. This is because the milk powder
Figure 6.3. Road map for using milk powders.