52 Chapter 2
the gastrointestinal tract. Branched chain
fatty acids reportedly prevent tumor forma-
tion in several animal models and human
breast cancer cells (Parodi, 2003 ;
Wongtangtintharn et al., 2004 ). Sphingolipids
may prevent cardiovascular disease and
tumor development. Similarly, omega - 3 and
omega - 6 polyunsaturated fatty acids sup-
press tumor development and lower plasma
cholesterol levels that consequently prevent
cardiovascular disease (Parodi, 2003 ).
These benefi cial fatty acids could be an
important factor in improving the nutritional
acceptability of milk fat in the future.
Furthermore, the manipulation of the ratios
of saturated fatty acids to unsaturated fatty
acids could improve the nutritional value of
milk fat.Enhancement via Culturing Milk
Milk can be cultured, providing consumers
with additional benefi cial properties. Gener-
ally, the microorganisms added to fermented
milk are probiotic bacteria, which are defi ned
by the Food and Agriculture Organization/
World Health Organization (FAO/WHO) as
live microorganisms that when administered
in adequate amounts confer a health benefi t
on the host. They are predominantly lactic
acid bacteria, which include Lactobacillus,
Bifi dobacterium , and Pediococcus species.
Several health benefi ts are scientifi cally
established including the alleviation of
lactose intolerance and the prevention of
rotavirus and antibiotic - associated diarrhea.
They have also been shown to treat allergies
including atopic eczema, stimulate the
immune system, prevent infl ammatory bowel
diseases, and inhibit Helicobacter pylori
(Vasiljevic and Shah, 2008 ).Bioactive Peptides
Bioactive peptides are derived from casein
and whey proteins in various ways: by enzy-
matic hydrolysis with digestive enzymes,thiamine, pantothenic acid, and folic acid.
Thiamine is a cofactor in carbohydrate
metabolism. B 2 has a role in the oxidation
of glucose, fatty acids, and amino acids, as
well as purine synthesis. Pantothenic acid
has a role in fatty acid metabolism and B 6 has
a role in protein metabolism. Folic acid is a
growth factor and has a role in DNA synthe-
sis. Vitamin B 12 is a growth factor and has
roles in blood formation and nerve tissue
functioning. Biotin is used in carbohydrate
metabolism as well as lipid, nucleic acid, and
protein synthesis.
Vitamin C is found in low levels in milk.
It is required for collagen formation, wound
healing, and absorption of non - heme iron,
and has a role as an antioxidant.
Specifi c Lipids
Several lipids in milk have potential benefi -
cial properties including conjugated linoleic
acids, sphingolipids, butyric acid, omega - 3
and omega - 6 polyunsaturated fatty acids,
branched fatty acids, and ether lipids. Milk
also contains the essential linoleic and
arachindonic fatty acids, which are not syn-
thesized by the body.
The concentration of conjugated linoleic
acids correlates with the concentration of
trans fatty acids in milk. However, the con-
centrations of conjugated linoleic acids are
inversely proportional to the concentration of
saturated fatty acids.
Several fatty acids have reportedly pre-
vented tumor proliferation including conju-
gated linoleic acids, branched chain fatty
acids, sphingolipids, butyric acids, and ether
lipids.
Specifi cally, conjugated linoleic acids
have been reported to prevent colon and
breast cancer, increase bone density, reduce
chronic infl ammation, normalize blood
glucose by increasing insulin sensitivity, and
exhibit strong antioxidant properties.
Phospholipids have roles in cell - ion inter-
actions and may improve fat absorption in