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area and produce enough milk for the average family (a good milker will
produce about a gallon a day); whereas the prospect of maintaining a
cow in a surburban backyard is usually more than the homeowner is
willing or able to cope with. Hence the growing popularity of the
''poor man's cow''.
3 As the interest in dairy goats and their products continues to
rise, it is apparent that many misconceptions, discrepancies and
exaggerated claims are being perpetuated. A comparison of cow and goat
milk seems to be in order, so that some prejudices against goat milk
may be erased. Also, while goat milk is somewhat unique, it is
certainly not a magical elixir.
4 One of the primary misconceptions concerning goat milk is that it
has a peculiar ''goaty'' odor or taste to it. This effect is produced
by the presence of the buck, whose scent glands are rather odoriferous
and may indeed cause the ''goaty'' type of milk people object to if he
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is present among the herd, especially at milking time. Does, however,
do not have the powerful odor of the buck and milk produced in the
absence of a buck should bear no objectionable odor.
5 Diet also plays a large role in the palatability of goat milk, as
well as cow milk. While cows are usually rather closely regulated as to
what they may eat and when, goats are often allowed to consume a great
variety of materials at any time, including browsing. This kind of
feeding may allow a certain ''off'' taste or smell to be transferred to
the milk, just as cows may produce a ''garlicky'' milk from some
spring pastures. What holds true for the cow also holds for the goat;
i.e. what comes out is based on what goes in! If goats and cows are
similarly managed, the smell and taste of both milks are quite
comparable.
6 Goat milk is similar to cow milk, in its basic composition. In
average, cow milk contains about 12.2 0ry matter (3.2DE9E:0001rotein, 3.6
fat, 4.7lactose and 0.7mineral matter). Goat milk contains about
12.1 dry matter (3.40001:0000rotein, 3.8 377794337129920800000000.000000at,
matter). These figures are only averages of course, as there are
considerable differences between breeds, and among individuals of a
breed. There are 6 breeds of dairy cows in the US, and 6 breeds of
dairy goats producing milk.
7 The Saanen is best known as the Holstein of the goat world,
producing a high quantity of milk with somewhat low fat levels. At the
other extreme is the Jersey of the goat world, the Nubian. This breed
produces a lesser amount of milk with a high fat content. The
Toggenburg, LaMancha, Oberhasli and Alpine fall somewhere in between.
8 However, there are also differences that give goat's milk a place
for special purposes. In summary:
++++MISSING DATA++++
9 Allergies appear to be more common than formerly thought,
especially in very young children. In an allergic type reaction, the
symptoms are produced by histamines, which are stored in body cells.
Histamines are released when triggered by a local stimulus.
Antibody-antigen type reactions that manage to find an anchorage on
cell walls trigger a release of histamine and produce the allergic
symptoms. Such a release brings on a congestion of the capillaries and
a flooding of the intracellular spaces by the lymphatic glands. The
stimulation of local nerve endings also occurs. People who display an
allergic reaction are usually more sensitive to the release of a given
amount of histamine and also tend to produce greater numbers of
antibodies to certain proteins.
10 Some of the so called ''sudden deaths'' of infants seem to be
related to allergic type responses, resulting in anaphylactic shock.
About 60f the infants in the US suffer allergic responses to cow's
milk. Of this number, however about only 14(of the 6) react to
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bovine serum present in cow milk. Most infants are allergic to various
constituents of cow milk which may also be present in goat milk.
Individuals who are allergic to bovine serum in cow milk will undergo
also an allergic reaction to a variety of dairy products that are made
with cow milk.
11 Other types of digestive upsets can result from milk due to a lack
of the lactosedigesting enzyme. While the presence of lactase is
universal in infants (up to 3 years), the presence of this enzyme in
adults is somewhat irregular and genetically determined.
12 Fat
One of the more significant differences from cow milk is found in
the composition and structure of fat in goat milk. The average size of
goat milk fat globules is about 2 micrometers, as compared to 21/2 -
31/2 micrometers for cow milk fat. These smaller sized fat globules
provide a better dispersion, and a more homogeneous mixture of fat in
the milk. Research indicates that there is more involved to the
creaming ability of milk than merely physical size of the fat globules.
It appears that their clustering is favored by the presence of an
agglutinin in milk which is lacking in goat milk, therefore creating a
poor creaming ability, especially at lower temperatures.
13 The natural homogenization of goat milk is, from a human health
standpoint, much better than the mechanically homogenized cow milk
product. It appears that when fat globules are forcibly broken up by
mechanical means, it allows an enzyme associated with milk fat, known
as xanthine oxidase to become free and penetrate the intestinal wall.
Once xanthine oxidase gets through the intestinal wall and into the
bloodstream, it is capable of creating scar damage to the heart and
arteries, which in turn may stimulate the body to release cholestrol
into the blood in an attempt to lay a protective fatty material on the
scarred areas. This can lead to arteriosclerosis. It should be noted
that this effect is not a problem with natural (unhomogenized) cow
milk. In unhomogenized milk this enzyme is normally excreted from the
body without much absorption.
14 Another significant difference from cow milk is the higher amount
of shorter-chain fatty acids in the milk fat of goats.
15 Furthermore, glycerol ethers are much higher in goat then in cow
milk which appears to be important for the nutrition of the nursing
newborn. Goat milk also has lower contents of orotic acid which can be
significant in the prevention of fatty liver syndrome. However, the
membranes around fat globules in goat milk are more fragile which may
be related to their greater susceptibility to develop off-flavors than
cow milk.
16 Protein
The protein composition of cow and goat milk is fairly similar,
although the typical major alpha-s-1- casein in cow milk is absent in
goat milk and the formation of casein curd under rennin action is
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different. The quality of curd is judged on two criteria:
1. Curd tension - a measure of the hardness or softness of the
curd. The softer the material, the more easily digestible it is. This
tension is largely a breed characteristic. Holsteins generally have
the softest curd in the bovine family. Cow range = 15-200 g, avg = 70
g. Goats range = 10-70 g, avg = 36 g.
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