Hindus nearly always boil their milk before using it, as the taste
of milk fresh from the cow is considered unpalatable. After boiling,
the milk is put in a pot and a little old curds added, when the whole
becomes _dahi_ or sour curds. This is a favourite food, and appears
to be exactly the same substance as the Bulgarian sour milk which is
now considered to have much medicinal value. Butter is also made by
churning these curds or _dahi_. Butter is never used without being
boiled first, when it becomes converted into a sort of oil; this
has the advantage of keeping much better than fresh butter, and may
remain fit for use for as long as a year. This boiled butter is known
as _ghi_, and is the staple product of the dairy industry, the bulk
of the surplus supply of milk being devoted to its manufacture. It
is freely used by all classes who can afford it, and serves very well
for cooking purposes. There is a comparatively small market for fresh
milk among the Hindus, and as a rule only those drink milk who obtain
it from their own animals. The acid residue after butter has been
made from _dahi_ (curds) or milk is known as _matha_ or butter-milk,
and is the only kind of milk drunk by the poorer classes. Milk boiled
so long as to become solidified is known as _khir_, and is used by
confectioners for making sweets. When the milk is boiled and some sour
milk added to it, so that it coagulates while hot, the preparation is
called _chhana_. The whey is expressed from this by squeezing it in a
cloth, and a kind of cheese is obtained. [29] The liquid which oozes
out at the root of a cow's horns after death is known as _gaolochan_
and sells for a high price, as it is considered a valuable medicine
for children's cough and lung diseases.