Dairy Ingredients for Food Processing

Butter and Butter Products 215

affected by its degree of unsaturation, but

may be extended by storing a low - moisture

product in opaque containers at a low tem-

perature to reduce autoxidation. A good

grainy texture due to the formation of large

milk fat crystals is an important quality attri-

bute of ghee; this can be encouraged by

seeding liquid ghee with a small quantity of

ghee grains. Ghee color and fl avor are source -

and process - dependant and tend to be deter-

mined by regional consumer preference.

Application of Milk Fat

in Products

Milk fat plays an important role in dairy

products and recombined dairy products such

as cream, butter, ice cream, cheese, and con-

centrated milks, but it is also a valuable

ingredient in a wide range of non - dairy prod-

ucts, primarily in the spreads, bakery, and

confectionery sectors of the food industry

(Table 9.4 ). As mentioned earlier, milk fat

confers a unique fl avor but its physical char-

acteristics, which may be modifi ed by frac-

tionation and blending, also infl uence the

texture, viscosity, fi rmness, and aeration

ability of food products.

The production of recombined dairy prod-

ucts is widely used in areas that cannot

sustain a local milk production industry. The

main ingredients required for such products

are non - fat milk solids, such as skimmed

milk powder, and a concentrated fat source —

AMF. These two ingredients may be blended

together in the correct proportions with a

variety of other ingredients to produce a

range of recombined dairy products. Care

must be taken to add the additional ingredi-

ents into the correct phase (for example,

emulsifi ers to the fat phase and salt to the

aqueous phase).

For all recombined products it is impor-

tant to use high - quality AMF or milk fat frac-

tions that have been prepared, packaged, and

stored to minimize oxidation and the devel-

opment of fl avor defects. Consideration also

variations of ghee produced throughout
Asia, the Middle East, and Africa, refl ecting
local preferences for the product (Sserunjogi
et al. 1998 ). Ghee is primarily used for
domestic culinary purposes, but it may be
incorporated into confectionery products,
used to garnish food, or fed to children for
therapeutic purposes.
Ghee is typically prepared by heating
cream or butter (from cows, buffaloes, cam-
els, goats, or sheep) to a suffi ciently high
temperature at which it is held until most of
the moisture has evaporated. The high tem-
perature produces carbonyls (aldehydes and
ketones), lactones, and FFA, which confer a
characteristic fl avor (varies between locales)
while improving shelf life by destroying
bacteria, inactivating enzymes, and forming
reducing compounds (Sserunjogi et al. 1998 ).
Over - heating, however, may lead to charring
of milk solids - not - fat, discoloration, and even
loss of desirable volatile fl avor compounds.
Typically, in larger scale commercial pro-
duction of ghee, fresh or cultured cream is
heated to 115 ° C (239 ° F) in stainless - steel
steam - jacketed vessels with continuous agi-
tation until caramelization produces a golden
brown color. When butter is the starting
material, it is usually fi rst heated to 60 ° C
(140 ° F) and then transferred as a liquid into
the steam - jacketed stainless - steel ghee boiler,
where it is heated with continuous agitation
to 90 ° C (194 ° F). Heating to a higher tem-
perature may be carried out to develop a
desirable color and fl avor in the fi nal product.
The use of ripened milk, cream, or butter has
been shown to produce an enhanced fl avor in
the ghee compared to the use of uncultured
raw materials, and this is thought to be due
to transfer of fl avor metabolites such as free
fatty acids and carbonyls from the aqueous
phase of the original cultured source
(Sserunjogi et al. 1998 ).
Ghee is generally packed into metal cans
with a lacquered inner surface, although lam-
inated pouches have also been used as a
cheaper alternative. The shelf life of ghee is