Milk may be defined as the fluid secreted in
the lacteal gland of female mammals for the nourishment of their young. This definition is satisfactory enough from the scientific point of view if
we add that the animals should be healthy. In other
words, we are not to understand by milk any fluid
which can be squeezed from the teat of the female.
Pus might be so obtained in certain states, and
while it would fulfil the first condition of the definition, it would be worse than useless for the
nourishment of the young, and it would not occur in
a healthy animal.
Cow's milk occupies a position of paramount
importance as an article of diet. It contains all
the elements requisite to maintain proper nutrition,
and although it can hardly be called a perfect food,
it approaches that ideal more than any other article
of diet. Thus dietetic and commercial considerations come in, and the simple definition given above is
not sufficient. It is necessary to have some stand-
and by which to judge of the quality of the milk
offered for sale. Cases of wilful adulteration
are not uncommon, and this, in conjunction with the
fact that cow's milk has so often to take the place
of mother's milk in the nursing of the infant, emphasises the desirability of, and indeed the necessity for some legal standard.
The necessity is admitted on all sides. The
difficulty is to determine what the standard is to
be. The difficulty is a very real one. Nature,
it is said, delights in variations. The truth of
the -aphorism is amply borne out in the case of milk,
for analysis of milks of different cows, or even of
milks of the same cows at different times,afford
striking differences. The variations are so great
that in the Farmer's Bulletin on "Milk as a food",
published by the United States Department of Agriculture, it is said "it is entirely possible that
one man may pay nearly twice as much as his neighbour for the same amount of nutriment when both buy
milk at the same price per quart ". The quality ofl
the milk depends on many things and to a great extent the variations are unavoidable. Thus it is
known that some breeds of cows yield quantity,
others quality; the morning milk is usually larger
in quantity, but poorer in quality; and the poorest
milk is yielded in the spring. The age, the feeding and the housing of the animal are also important factors in determining the quantity and the
quality of the yield of milk.
We, therefore, require to have something more
definite than "the fluid secreted in the lacteal
gland of the cow". The natural definition must
give way to a more or less artificial one. A purchaser is entitled to receive the article for which
he asks and pays, and in the case of milk, he ought
to receive a fluid approximating in composition to
the normal article. If this be admitted, then the
only possible definition would seem to be one stating what the normal article really is. Such a
definition can only be obtained after an analysis
of many samples of milk taken from healthy animals
under varying conditions. In this way one arrives
at a correct idea as to the average composition of
milk and after making due allowances, a limit is
fixed,below which no milk offered for sale should
fall. Such is the basis of the present legal
standard of milk.
The only objection that can be urged is that
on occasion an apparently healthy cow will give
milk which is below the legal standard, and it is
held to be a hardship that the vendor should be punished for selling milk which satisfies the natural
definition. These abnormal milks are rare, and in
any case,commercially,milk is almost invariably the
mixed milk of a herd and therefore the low milk of
one cow will be counterbalanced by the mixture of
extremes.
The position adopted by the state is perfectly logical. Milk is defined as a fluid of a certain composition and the vendor is held responsible
for what he sells. If he sells milk which falls
below the standard fixed on an analysis of many
thousand samples, he must suffer the consequences.