Agriculture Reference
In-Depth Information
Table 14.5
Concentration of total N, NPN, and phosphate in goat and cow milk and soy-based infant
formulae
1
.
Total N
NPN
P
2
O
5
¯
¯
¯
Milk
N
2
S D
S D
S D
Goat Milk
Alpine
25
.390
c
.032
.048
b
.008
.166
a
.020
Nubian
25
.556
a
.013
.061
a
.013
.212
a
.015
Cow Milk
Holstein
25
.392
c
.058
.033
c
.002
.173
a
.022
Jersey
25
.505
b
.043
.038
c
.004
.211
a
.118
Formula Milk
Brand A
5
.227
d
.026
.020
d
.003
.211
a
.008
Brand B
5
.259
d
.016
.019
d
.003
.192
a
.053
a,b,c,d
Means with different superscripts within a same column are signifi cantly different (P < .01).
1
Expressed in g/100 ml.
2
Number of determinations per mean value.
Source: Park, 1991 .
goat milk is about 0.4% units lower than in cow milk (Park,
2006). Goat milk has about 10 times more oligosaccha-
rides than cow milk, which closely resembles that of
human milk. This is of special interest to infant nutrition,
since goat milk oligosaccharides have important functions
in human nutrition. A larger variety of acidic and neutral
oligosaccharides are present in goat than in cow or sheep
milk.
inversely related to its mineralization (Remeuf and Lenoir,
1986 ).
Vitamins
Goat milk supplies adequate amounts of vitamin A and
niacin, and an excess of thiamine, ribofl avin and pantothe-
nate in addition to protein, Ca, and P for human infants in
relation to FAO-WHO requirements (Table 14.3). Vitamin
A content of goat milk is higher than in cow milk. Goat
milk is white in contrast to most cow milk (except for
white Ayrshire milk), because goats convert all β - carotene
(yellow color) into vitamin A (no color) in milk. Because
of rumen synthesis, vitamin B content in goat and cow
milk is mainly independent of diet. Goat milk, however, is
defi cient in folic acid and vitamin B
12
as compared to cow
milk (Jenness, 1980), which contains about 5 times more
folate and vitamin B
12
than goat milk. Folate is necessary
for the synthesis of hemoglobin. Goat and cow
milk are also defi cient in pyridoxine (B
6
), vitamin C and
D, indicating a need for supplementation in human
nutrition.
Minerals
Goat milk contributes importantly to the mineral nutrition
of people in developing and underdeveloped countries,
especially for calcium (Ca) and phosphorus (P). Goat milk
contains about 134 mg Ca and 141 mg P/100 g of milk
(Table 14.3). Human milk contains only one-fourth to one-
sixth of these minerals as compared to goat milk. Goat
milk has higher calcium, phosphorus, potassium, magne-
sium, and chlorine, but lower sodium and sulfur content
than cow milk.
A close inverse relationship exists between lactose
content and the molar sum of sodium and potassium
content in milk of goat or other species (Park and Chukwu,
1988). Chloride is positively correlated with potassium
and negatively with lactose. The levels of major minerals
in milk do not usually fl uctuate with diet, but they can vary
depending on breed, individual animals, and stage of lacta-
tion, whereas trace mineral content of goat milk may be
infl uenced by the diet and other factors. The casein micelle
in goat milk has a lower degree of hydration, which is
Minor Constituents in Goat Milk
Bioactive components in milk of different species includ-
ing goat milk have been studied by numerous researchers.
These compounds can be released by enzymatic hydrolysis
of milk proteins, exerting specifi c biological activities,
such as antihypertensive, antimicrobial, opioid, antioxi-
dant, immunomodulant, or mineral-binding capacity. Such
