consumption (home produce plus imports) 566,441 tons, the
consumption per head of population being 19.2 lb. per annum. In
butter, as in most other articles of food, adulteration with
water is the most common, most profitable, and least risky
form of fraud. Great fortunes are thus made out of water.
There is an altogether different class of butter adulteration
which concerns itself with the substitution of other fatty
matters for the whole or part of the really valuable portion
of the butter- fat. Margarine is the legalized and therefore
legitimate butter surrogate, prepared by churning any
suitable fat with milk into a cream, solidifying the latter
by injection into cold water and working the lumps together,
precisely as is done in the case of the churned cream of
milk. The substitution of margarine for butter is frequent,
in spite of all legal enactments directed against this fraud,
the semblance between butter and margarine being so great
that a trained palate is necessary to distinguish the two
articles. Much more frequent and much more difficult to deal
with is the sale of mixtures of butter and of margarine.
In order to show the difficulties inherent to this subject,
it will be necessary to consider the chemical nature of
butter-fat, and to compare it with other fats that may enter
into the composition of margarine. Butter-fat is butter freed
from water, curd and salt and extraneous matter. Like the
greater number of natural fats it consists of a mixture of
triglycerides, that is, combinations of glycerin with substances
of the nature of acids. These acids, in the case of fats
other than butter-fat, are mainly oleic, palmitic and stearic
acids. Butter-fat, in addition to these, contains other
acids which sharply distinguish it from the vast majority
of other fats and, with the exception of cocoa-nut oil, from
those substances which are or may be used to mix with butter,
by the circumstance that a considerable proportion of its
acids, when separated by chemical means from the glycerin, are
readily soluble in water, or may be easily volatilized either
alone or in a current of steam, whereas the acids separated
from the foreign fats are practically both insoluble and
non-volatile. This fundamental principle serves at once to
distinguish, for example, between butter and margarine, and
has been made use of by analysts not only for this purpose
but also with a view to determine the relative amounts of
butter and margarine in a mixture of these substances. Thus
butter-fat contains about 88%, more or less, of ``insoluble
fatty acids,'' while margarine contains about 95.5%; 5
grammes of butter-fat when chemically decomposed yield an
amount of volatile fatty acids which requires about 26 cubic
centimetres (more or less) of deci-normal alkali solution for
neutralization, while margarine requires mostly less than 1
cubic centimetre (Wollny or Reichert-Meissl method). There
are other differences between the two kinds of fat: the
specific gravity of butter-fat is higher than that of most
other fats; its power of refracting a ray of light is less;
the ``iodine absorption'' of butter-fat is smaller than that
of many other fatty matters, and so on. But the composition
of perfectly genuine butter-fat varies within somewhat wide
limits. The milk from a cow fed on good and ample food in
warm weather yields a fat that is rich in characteristic
butter-constituents, while a poorly fed animal, kept in the
open till late in the autumn, when the nights are cold, gives
milk exceptionally poor in fat, the differences expressed as
``insoluble fatty acids'' lying between 86 and 91%, and in
volatile acids, expressed as ``Wollny'' numbers, between 18
and 36. Generally, therefore, summer butter is rich and autumn
butter poor in volatile acids, or, geographically, Australian
butter is more frequently high, Siberian often exceedingly low
in these acids. The food of the animal also may, under certain
conditions, yield a notable proportion of its fatty matter
to the butter; cows that have, for instance, been fed upon
large quantities of cotton-seed cake yield butter in which the
cotton-seed oil may be traced, and the same holds good with
other fatty foods. All these, and other circumstances, combine
to render the detection of small quantities of foreign fats
that have been fraudulently added to butter almost a matter of
impossibility. This is perfectly well known to unscrupulous
butter dealers, and an enormous amount of adulteration is known
to be practised. Even small amounts of adulteration could,
nevertheless, often be discovered while margarine manufacturers
employed considerable proportions of vegetable oils in their
products, some of these oils furnishing characteristic chemical
reactions allowing of their discovery. Here some firms of
margarine manufacturers came to the aid of the butter-mixer
and produced margarine containing nothing but animal fat,
so-called ``neutral'' margarine being freely offered for
fraudulent purposes. There is one fat besides butter which
contains ``volatile fatty acids,'' namely, cocoa-nut oil.
Since means have been found to deprive this fat of its strong
cocoa-nut odour and taste, it has largely been used in the
adulteration of butter, and margarine containing Cocoa-nut
oil and other fatty substances has freely been manufactured
and sold specially for butter adulteration. The seat of this
class of fraud is mainly in Holland. Analysts happily found
means to detect this oil when present above 10%, and numerous
prosecutions made mixers more careful. Abundant evidence,
however, exists showing that the simultaneous addition of
water or milk so as to keep the water limit below 16% and
that of margarine entirely composed of animal fats below 10%
leaves a large margin of profit with a very small chance of
detection. For the moment at least analysis has had the worst
of it in the battle between honesty and ``business methods.''
Margarine itself is a legitimate article of commerce (when
sold with due notice to the purchaser), but is frequently
adulterated. As regards the fats used in its manufacture
there does not exist any legal restriction, and as long
as the fat is in a state fit for human consumption the
manufacturer can make whatever mixture he pleases. In general
there is no reason to think that any bad or disgusting fats
are finding their way into the factories, which in most
countries are under proper supervision; the old stories about
recovered grease from all sorts of offal are quite without
foundation. But a considerable percentage of solid paraffin
has been met with as an admixture of the fatty part of
margarine. As the fatty portion of the article is the
only one of value, some manufacturers make great efforts
to produce margarine with as small a percentage of fatty
matter as possible, either by incorporating excessive amounts
of water or of milk--margarines with over 30% of water
being met with--or by introducing sugar, glucose, starch,
gelatinous matter, in fact anything that is cheaper than
fat. The English law imposes a limitation upon the percentage
of butter-fat that may be contained in margarine, but at
present at least the tendency of manufacturers is all for
having as little butter or other valuable fat in margarine
as is practicable, and not to err on the other side. For the
purpose of facilitating the discovery of margarine when it has
been fraudulently added to butter, some countries (Germany,
Belgium, Sweden) insist upon the use of from 5 to 10% of
sesame oil (from the seed of Sesamum orientale or indicum,
belonging to the family of Bignoniaceae) in the manufacture
of such margarine as is to be consumed within the countries in
question. This oil yields a characteristic red colour when
it, or any mixture containing it, is shaken with an hydrochloric
solution of either sugar or furfurol, and is intended to serve
as an ``ear-marking'' substance. The addition of a little
starch or arrowroot, easily discoverable chemically or by the
microscope, is also required by Belgium, but in the absence
of any international agreement these ear-marking additions
are of little practical use. It is, however, interesting to
point out that, while complying with the regulations of the
governments, margarine manufacturers of the countries named
have found an easy way of rendering the regulations quite
nugatory: they add methyl-orange, a colouring matter which
itself produces a red colour with acid and quite obscures
the real colour obtained by the official test for sesame oil.
Cheese may be legitimately made from full-milk, milk that
has been enriched by addition of cream, or from milk that
has been more or less skimmed. It varies consequently very
widely in composition, so-called cream cheese containing
not less than 60% of fat; Stilton upwards of 40%; Cheddar
about 30%; Dutch, Parmesan and some Swiss and Danish less
than 20%. The amount of water varies with the kind and age
of the cheese and may be as low as 20 and as high as 60%.
Under these circumstances it is impracticable to lay down
any hard-and-fast rules as to the composition of cheese.
When, however, cheese is made from skimmed milk and the
fat is replaced by margarine, as is the case in so-called
``filled'' or margarine cheeses, the sale of these amounts to an
adulteration, unless the presence of the foreign substance is
declared. It may at first sight appear strange that the person
who robs milk of its most valuable portion, the cream, may
prepare a legitimate article of food from the remainder, while
he who to that remainder adds something to replace the fat does
an illegitimate act, but it must be taken into consideration
that the replacement is frequently made with fraudulent
intent and that the ordinary purchaser cannot by taste or
smell distinguish the adulterated from the genuine article,
while there is no difficulty in recognizing skim-milk cheese.
Lard.--Between the years 1880 and 1890 a gigantic fraudulent
trade in adulterated lard was carried on from the United
States. A great proportion of the American lard imported into
England was found to consist of a mixture of more or less real
lard with cotton-seed oil and beef-stearine. Cotton-seed oil
is one of the cheapest vegetable oils fit for human consumption,
beef-stearine the hard residue obtained in the manufacture
of oleo-margarine after the more fluid fat has been pressed
from the beef fat. These mixtures were made so skilfully by
large Chicago manufacturers that for some years they escaped
detection. A bill introduced in 1888 into the American
Senate to stop this imposture directed general attention to
the subject, and energetic measures, taken both in America
and in England, quickly put an end to it. From the memorial
presented in the United States Senate in support of the
bill, it appeared that in about 1887 the annual production
of lard in the States was estimated at 600 million pounds,
of which more than 35% was adulterated. Compounds were made
containing only a small quantity of lard or none at all, yet
were sold as ``choice refined lard'' or under other eulogistic
names. Many lard substitutes, chiefly made from cotton-seed
oil, are still met with, but are mostly sold in a legitimate
manner. From the germ of maize--which must be separated
from the starchy portion of the seed before the latter can be
manufactured into glucose--the oil (maize-oil) is expressed,
and this now is used as a lard adulterant, its detection
being far more difficult than that of cotton-seed oil.
Oils.--For very many years all oils were considered to
