The evening times. [volume] (Grand Forks, N.D.) 1906-1914, 1906-07-28
Home and Farm

We all hear a great deal about the
poisons with which our daily food Is
adulterated. Simple methods for the
detection of some forms of food adul-
iteration are presented by two govern
ment officials belonging to the bureau
of chemistry. United States depart
ment of agriculture: w. D. Bigelow,
chief division Of foods; Burton j.
Howard, chief microchemical labora-
tory.
Many manufacturers and dealers in
foods have the ordinary senses SO
highly developed that by their aid
alone they can form an intelligent
opinion of the nature of product, or
of the character. and sometimes even
of the proportion, of adulterants pres
ent. This is especially true of such
articles as coffee. wine. salad oils,
flavOring extracts, butter and milk.
The housewife finds herself constant
ly submitting her purchases to this
test. Her broad experience develops
her senses of taste and smell to a
high degree, and her discrimination is
often sharper and more accurate than
she herself realizes. The manufac-
turer who has developed his natural
senses most highly appreciates best
the assistance of collaboration of the
chemist. who can often come to his
relief when his own powers do not
avail. So the housewife. by a few
simple chemical tests, can broaden
her field of vision and detect many
impurities that are not evident to. the
senses. All of the tests here described
may be performed with utensils found
in any well-appointed kitchen.
Detection Of SsllcyHc Acid.
The determination of salicylic acid
can best be made with liquids. Solid
and semi-solid foods, such as jelly,
should be dissolved, when soluble. in
sufficient water to make them thinly
liquid. Foods containing insoluble
matter. such as jam, marmalade and
sausage, may be macerated with wa
ter and strained through a piece of
white cotton cloth. The maceration
may be performed by rubbing in
teacup or other convenient vessel with
heavy spoon.
Salicylic acid is used for preserving
fruit products of all kinds, including
beverages. 1t is frequently sold by
drug stores as fruit acid. Preserving
powders consisting entirely of salt
cylic acid are often carried from
house to house by agents. 1t may be
detected as follows:
Between two and three ounces of
the liquid obtained from the fruit
products, as described above, are
placed in narrow bottle holding five
ounces, about quarter of a tea
spoonful of cream of tartar Tor, bet
ter, few drops of sulphuric acid) is
added, the mixture shaken for two or
three minutes, and filtered into q Sec
ond small bottle. Three or four table,
spoonfuls of chloroform are added to
the clear liquid in the second bottle
and the liquids mixed by somewhat
vigorous rotary motion. poured into
an ordinary glass tumbler and al
lowed to stand till the chloroform
settles out in the bottom. Shaking is
avoided, as it causes an emulsion
which is difficult to break up AS
much as possible of the chloroform
layer (Which now contains the SAIL
cylic acid) is removed without any
admixture of the aqueous liQuid) by
means of a medicine dropper and
placed in test tube or small bottle
with about an equal amount of water
and small fragment little
larger than pinhead-of iron alum.
The mixture is thoroughly shaken and
allowed to stand till the chloroform
again settles to the bottom. The
presence of salicylic acid is then in
dictated by the purple color of the up
per layer of liquid.
Detection Of Benxoic Acid.
Benzoic acid also is used for pre-
serving fruit products. Extract the
sample with chloroform as in the case
of salicylic acid; remove the chloro-
form layer and place it in a white
saucer, or, better, in a plain glass
dish. Set basin of water-as warm
as the hand can bear-on the outside
window ledge and place the dish con-
tanning the chloroform extract in it,
closing the window until the chloro-
form has completely exaporated. In
this manner the operation may be
conducted with safety even by one
who is not accustomed to handling
chloroform. In warm weather the