The importance of goat rearing in providing nutritional
and financial sustenance to the economically weaker
sections of the society is well recognized in developing
countries. Goats have the ability to thrive under diverse
climatic conditions and withstand extreme vagaries of
nature. India possesses the largest number of goats, which
contribute three million metric ton of milk.
Adequate processing of raw milk of goat followed by
value addition will result in doubling of return from goat
milk apart from increased shelf life and reduced volume of
the product resulting in lower transportation cost than
that is obtained as of now.
However, certain peculiar characteristics of goat milk
like relatively smaller size of the fat globules, lower
heat stability, soft curd and the typical "goaty odour"
have to be taken care of while dealing with goat milk
especially in processing and marketing.
Physico-chemical properties of Goat Milk
The specific gravity of goat and cow milk is almost
similar in nature (the specific gravity ranges between
1.028 and 1.030). The viscosity is 13.4 mP at 27°C, which
is marginally lower than cow milk, but the value of
refractive index lies in between that of cow and buffalo
milk. The electrical conductivity ranges between 0.0101 and
0.0188 ohm-1 cm-1. The titratable acidity expressed as
percentage of lactic acid ranges between 0.11 and 0.18,
which is again within the range encountered in cow
The mean pH value of goat milk varies from 6.5 to 6.9
whereas it is 6.6 to 6.8 in case of cow milk. The value of
curd tension test (which measures the resistance in g which
a special multi bladed curd knife encounters in its passage
through the coagulated milk) is well below than that of cow
milk. The average value with pepsin calcium chloride is 36.
This is responsible for better digestibility in goat milk
as compared to cow milk.
Lipids of Goat Milk
The peculiar character of the fat globules of goat milk
is that they are smaller in size when compared to that of
cow milk. The size of fat globules range from 2 to 20
micron in buffalo milk and 1 to 10 micron in cow and goat
milk. But the number of fat globules less than 5 micron is
62% in cow milk whereas it is approximately 83% in goat
milk, which really matters; i.e. from nutritional point of
view, the number of fat globules less than 5 micron is very
important. But this creates problem in butter making.
Further, due to lack of agglutinins in goat milk, the fat
globules do not clump together when it is chilled.
The fatty acid composition reveals the presence of
higher concentration of short and medium chain fatty acids,
which are thought to be responsible for the characteristic
"goaty odour" in goat milk. But, the silver lining is that
they are amenable to heat treatment and hence
pasteurization of milk removes this defect.
Another group of scientists refute this claim and state
that the presence of buck during milking of does is
responsible for the absorption of the odor produced from
the glands of buck. But however, this hypothesis is not yet
Proteins of Goat Milk
The cow milk and goat milk do not differ significantly
as for as the protein percentage is concerned. One group of
scientists is of the view that goat milk lacks a-S1 casein
whereas it is countered by their opponents.
However, there is significant difference between cow and
goat milk, with regard to the size of the casein micelle.
The casein micelle in cow milk is small (60-80nm) when
compared to goat milk casein micelle, which range between
Minerals and Vitamins
The mineral content varies from 0.70 to 0.85 %. When
compared to human and cow milk, goat milk contains more
calcium, phosphorous and potassium. The vitamin content is
similar to that of cow and human milk.