of nitric acid on mercury, a reagent being prepared by dissolving 1
c.c. of mercury in 12 c.c. of cold nitric acid of 142 sp. gr. When
this is shaken with the oil in a wide-mouthed stoppered bottle in the
proportion of 2 c.c. of reagent to 50 c.c. of oil, the shaking being
repeated at intervals of ten minutes for two hours, and the temperature
being kept constant at not less than 25° C., a bright lemon-yellow
coloured solid mass is obtained with olive oil. The products of the
reaction with almond, lard, sperm, and arachis oils are also solid, but
those yielded by rape, sesame, cotton-seed, sunflower, cod-liver, and
porpoise oils have a consistency resembling that of butter, while those
from linseed and other drying oils are liquid.
COTTON-SEED OIL
There are two well-known tests for this oil, those of Bechi and
Halphen, both of which have undergone various modifications.
Bechi’s, or the silver nitrate test, requires the preparation of two
solutions: (1) containing 1 grm. of silver nitrate dissolved in 200
c.c. or alcohol (98 per cent. by volume), to which is added 40 c.c. of
ether and 0.1 grm. of nitric acid; and (2) a mixture of 15 c.c. of rape
oil with 100 c.c. of amyl alcohol. Ten c.c. of the oil to be tested
are mixed in a test tube with 1 c.c. of solution (1), and then shaken
with 10 c.c. of solution (2). The mixture is now divided into two equal
parts, and one-half immersed in boiling water for fifteen minutes,
after which it is withdrawn and compared with the unheated portion. In
the presence of cotton-seed oil a reddish-brown coloration is developed.
_Halphen’s Test._—Equal parts of the oil or fat (or its fatty acids),
amyl alcohol, and a 1 per cent. solution of sulphur in carbon
bisulphide, are heated together in a test tube placed in a boiling
water bath until effervescence ceases, and then transferred to a
boiling brine-bath for about an hour, when, if cotton-seed oil is
present, a pink coloration is produced. The reaction may be rendered
much more rapid, according to Rupp (_Zeit. Untersuch. Nahr. Genussm._,
1907, xiii., 74), by heating the mixture in a stoppered flask.
The production of a coloration with Bechi’s or Halphen’s reagent does
not invariably prove the presence of cotton-seed oil, as the pure fat
of animals fed with cotton-seed cake, even some long time previously,
has been found to give the reaction. On the other hand, failure to
obtain a reaction does not prove the absence of cotton-seed oil, since
heating the oil to 250° C. causes it to give negative results in these
tests.
ARACHIS OIL
The great similarity in the properties of this oil and olive oil
renders some means of distinguishing one from the other necessary,
and a process for the purpose has been based on the different
chemical composition of the fatty acids, the arachis oil containing a
considerable proportion of arachidic and lignoceric acid.
This arachidic acid (the term also being used to include the lignoceric
acid) may be determined by the following process due to Renard and
modified by Lewkowitsch:—About 10 grms. of the oil are saponified
with alkali, as described under the “titre test,” the soap dissolved
in water, excess of alkali neutralised with acetic acid, and the lead
salts of the fatty acids precipitated by addition of a solution of lead
acetate, filtered off, and extracted with ether, all but the palmitate
and arachidate being dissolved. These latter are decomposed with
hydrochloric acid, the fatty acids separated from lead chloride, and
dissolved in 50 c.c. of hot 90 per cent. alcohol.
On cooling this solution, arachidic acid will crystallise out if
arachis oil is present, and the amount of arachidic acid may be
estimated, if desired, by filtering it off, and washing it twice with
10 c.c. of 90 per cent. alcohol, and once with alcohol of 0.890 sp.
gr. The residue on the filter is now extracted with boiling absolute
alcohol in which arachidic acid is soluble, the solution evaporated to
dryness, and the arachidic acid weighed.
This amount has to be corrected by the addition of 0·0025 grm. for each
10 c.c. of 90 per cent. alcohol used in the crystallisation and washing
if the treatment has been carried out at 15° C., or 0·0045 for 10 c.c.
if it was done at 20° C. Arachis oil contains about 5 per cent. of
arachidic acid, so that twenty times the total amount of arachidic acid
represents the quantity of arachis oil in the sample under examination.
The melting-point of arachidic acid is 71°-72° C.
BUTTER
An analysis of butter for the purpose of the Food and Drugs Act should
comprise determination of the water and examination of the fatty
matter, together with tests for colouring matter and preservatives. In
addition, estimations of the casein, ash, and salt are also sometimes
made.
The effect of heating a little of the sample in a spoon is a useful
rough indication of its purity. Pure butter produces considerable foam,
and turns brown, but butter substitutes do not foam appreciably, and
unless specially prepared to do so (see Chapter IV. pp. 45 and 71), do
not become brown.
_Water._—The determination of water may be made by weighing out about 5
grms. of the butter in a platinum dish and placing it in a hot-air oven
at a temperature of 100°-105° C., the drying being continued until the
weight is constant.
_Examination of the Fat._—A quantity of the butter fat is prepared by
heating about 50 grms. of the sample on the top of a water-bath until
it has completely melted, and the water and casein have separated to
the bottom, when the clear fat is decanted off and filtered through a
dry, warm filter paper. The filtered fat should be clear and bright,
and is then ready for examination.
Many of the general methods already described for the examination of
oils and fats are applicable, and furnish useful information as to the
purity of butter. Such, for example, are the specific gravity, the
saponification value, the refractive power, and Valenta’s acetic acid
test, the variations in which are discussed on p. 102.
_Refractive Power._—The instrument most usually employed is the Zeiss
butyro-refractometer, which consists of an Abbé double prism, which
opens for the reception of a few drops of the melted and, preferably,
filtered fat. A telescope is attached for reading the refraction on an
arbitrary scale graduated from 5°-105°. The prism should be maintained
at 40° C. while the observation is being made. At this temperature the
reading for pure butter is usually about 35°-38°. If the temperature is
above 40° subtract 0·55° for each degree above, and if below 40° C. add
0·55° for each degree below.
_Valenta’s Acetic Acid Test._—Reference has already been made to the
value of this in the examination of butter fat (p. 48). The mixture of
2·75 grms. butter fat and 3 c.c. glacial acetic acid is warmed to 40°
C., when, if the butter fat is pure, the mixture should become clear.
If this is the case, the liquid is now allowed to slowly cool down with
constant stirring with a thermometer until it just becomes turbid,
which should take place at about 30°-40° C.
With the exception of the determination of the refractive power these
methods of examination have now very largely given place to processes
based on the presence of volatile fatty acids in butter, and on their
differentiation from the volatile fatty acids found in cocoanut oil
(see pp. 50 _et seq._).
[Illustration: FIG. 1.]
The modification of the Reichert process suggested by Wollny was, in
its essential details, that adopted for the determination of butter in
margarine by a Committee of the Society of Public Analysts appointed
in 1900 to confer with the Principal of the Government Laboratory. The
details of this process, which was formerly, until the large increase
in adulteration of butter with cocoanut oil, or margarine containing
cocoanut oil, the chief method for the examination of butter, are as
follows (_Analyst_, 1900, 311):—
Five grms. of the melted and filtered fat are weighed into a 300 c.c.
flask, of the form and size shown in the figure, and 2 c.c. of a
solution prepared by dissolving 98 per cent. sodium hydroxide in an
equal weight of water, taking care to prevent absorption of atmospheric
carbon dioxide, and 10 c.c. alcohol (92 per cent.) are added. The
mixture is heated under a reflux condenser connected with the flask
by a T-piece for fifteen minutes in a bath containing boiling water.
The alcohol is distilled off by heating the flask on the water-bath
for about thirty minutes, or until the soap is dry. One hundred c.c.
of hot water, which has been kept boiling for at least ten minutes,
are added, and the flask heated until the soap is dissolved. Forty
c.c. of N/1 sulphuric acid, and three or four fragments of pumice or
broken pipe-stem, are added, and the flask is at once connected with
a condenser by means of a glass tube 7 mm. wide and 15 cm. from the
top of the cork to the bend. At a distance of 5 cm. above the cork
is a bulb 5 cm. in diameter. The flask is supported on a circular
piece of asbestos 12 cm. in diameter, having a hole in the centre 5
cm. in diameter, and is first heated by a very small flame to melt
the insoluble fatty acids, though the heat must not be sufficient to
cause the liquid to boil. The heat is increased, and, when fusion is
complete, 110 c.c. of the liquid are distilled off into a graduated
flask, the distillation lasting about thirty minutes (twenty-eight
to thirty-two minutes). The distillate is shaken, 110 c.c. filtered,
transferred to a beaker, 0·5 c.c. of an alcoholic phenol-phthalein
solution (1 per cent.) added, and the filtrate titrated with N/10
sodium hydroxide or barium hydroxide until pink. A blank experiment is
carried out in precisely the same way, using the same reagents, and
omitting the fat, and the amount of N/10 alkali required to neutralise
this distillate should not exceed 0·3 c.c. The difference between
the volumes of alkali required with the butter fat and in the blank
determination, multiplied by 1·1, gives the Reichert-Meissl-Wollny
value.
The improvements in the methods of refining cocoanut oil during recent
years have led to the addition of considerable quantities of cocoanut
oil to edible fats, and thus has somewhat reduced the value of this
process for distinguishing pure from adulterated butter, owing to
the fact already mentioned, that cocoanut oil contains a distinct
quantity of volatile fatty acids. A very large number of methods have
been proposed for detecting cocoanut oil in butter, and such terms
as “silver value,” “caprylic acid value,” “oxygen equivalent,” have
appeared in the literature of the subject.
Probably the most valuable of all these tests is one devised by
Polenské (_Zeit. Untersuch. Nahr. Genussm._, 1904, vii. 273-280), which
is based upon the determination of the volatile insoluble fatty acids
that distil over in the Reichert-Wollny process. This method, which is
known as the Reichert-Wollny-Polenské process, is now very generally
employed for the analysis of butter, but to obtain concordant results
it must be carried out strictly under the specified conditions and in
an apparatus of the form and dimensions shown in the figure (Fig. 2).
The details of the process are as follows:—
Five grms. of the clear butter fat are weighed out into a 300 c.c.
flask, and saponified as described on p. 111, with 20 grms. glycerin
and 2 c.c. of a 50 per cent. aqueous solution of sodium hydroxide, the
heating being effected with a Bunsen burner. When saponification is
complete and the mixture perfectly clear, it is allowed to cool down
below 100° C., and the soap dissolved in 90 c.c. of water. To this
solution, which should be clear and almost colourless, are now added 50
c.c. of dilute sulphuric acid containing 2·5 per cent. sulphuric acid
and some fragments of pumice, and the flask attached to the condenser.
The distillation is now proceeded with as usual, the heat being so
regulated that 100 c.c. of distillate passes over in nineteen to twenty
minutes, and the temperature of the condensing water is between 18°
and 20° C. As soon as 110 c.c. of distillate have been collected the
receiver is changed, and a 25 c.c. cylinder put in its place. The
receiver is now transferred (care being taken to mix its contents as
little as possible) to a water-bath at a temperature of 10° C., where
it is kept for ten minutes, the surface of the water being just above
the 110 c.c. mark. The insoluble fatty acids rise into the neck of the
flask, and, in the case of butter, are in the form of solid, opaque
granules, and with pure cocoanut oil in the form of clear, oily drops.
The latter are also obtained in the case of mixtures containing more
than 10 per cent. of cocoanut oil. The liquid is mixed and filtered,
the Reichert-Wollny value being determined on the filtrate by titration
with N/10 alkali.
The condenser, cylinder, and receiver are now washed with 18 c.c. of
water, the washings being passed through the filter paper, and the
insoluble fatty acids remaining on the filter dissolved in alcohol.
The solution obtained is titrated with N/10 barium hydroxide solution,
using phenol-phthalein as indicator, the number of c.c. required being
termed the “new butter value” of the fat.
This value was stated by Polenské to range, for pure butters having
Reichert-Meissl values of 23·3-30·1, from 1·5-3·0, and for cocoanut
oils having Reichert-Meissl values of 0·8-7·7, from 16·8-17·8.
Mixtures with Reichert-Meissl values between 23 and 27 gave “new
butter values” of from 1·6-1·9, a rise of 1·0 in the Reichert-Meissl
figure corresponding with an increase of 0·1 in the “new butter
value,” and each per cent. of cocoanut oil increasing the new butter
value by 0·1 above that given by a genuine butter possessing the same
Reichert-Meissl value. By this method it is possible to detect the
presence in butter of 10 per cent. and upwards of cocoanut oil.
A process similar in principle, but differing in method has been
proposed by Muentz and Coudon (_Ann. d. l’Inst. Agron._, 1904, iii.,
Part I.; _Analyst_, 1905, 155). In this, 10 grms. of the fat, melted
and weighed at 60° C., are placed in a cylindrical vessel, and
saponified by first stirring for ten minutes with 5 c.c. of potassium
hydroxide solution, containing 120 grms. potassium hydroxide in 100
c.c., and then heating to 70°-80° for twenty minutes. The saponified
fat is washed into a distilling flask with 200 c.c. of water, gently
warmed until solution is complete, and the fatty acids liberated by
adding 30 c.c. of phosphoric acid (sp. gr. 1·15), any carbon dioxide
being removed by connecting the vessel with a pump for ten minutes.
[Illustration: FIG. 3.]
The volatile fatty acids are then distilled off in the apparatus shown
in Fig. 3, and to obtain comparative results, strict adherence to the
form and dimensions given must be made. Two hundred c.c. are distilled
over, the heat being regulated so that this takes about one and a half
hours, and the distillate is allowed to stand until the following day,
when it is filtered through a wet paper, the flask washed with 5 c.c.
of water, which is also passed through the paper, and the soluble fatty
acids titrated with standardised lime-water, with phenol-phthalein as
indicator.
The filter is now washed with four successive quantities of 5 c.c. of
alcohol, poured on drop by drop, and the washings collected in the
receiver originally used. The condenser is next rinsed, first with 20
c.c. of alcohol, which should fill the tube when closed at its lower
end, and a second time with 5 c.c. of alcohol, these washings being
added to the remainder, and the whole titrated with the standard
lime-water.
The results of both titrations are expressed as butyric acid, and the
ratio
insoluble acids
———————————————— × 100
soluble acids
for pure butter should lie between 10 and 15, whilst for cocoanut oil
it is 250-280. For butter containing 10 per cent. of cocoanut oil the
figure is 19·8, and 15 per cent. cocoanut oil 24·1, for 20 per cent.
cocoanut oil 27, and for 50 per cent. cocoanut oil 73·1. It is claimed
that by this process the presence in butter of as little as 5 per cent.
of cocoanut oil can be detected with certainty.
Two methods have been proposed, based on the precipitation of insoluble
silver caprylate: (1) by Kirschner (_Zeit. Untersuch. Nahr. Genussm._,
1905, ix. 65-70), and (2) by Wijsman and Reijst (_Zeit. Untersuch.
Nahr. Genussm._, 1906, xi. 267-271).
In the former process, 5 grms. of the fat are treated by the
before-mentioned Reichert-Meissl-Wollny process so far as neutralising
100 c.c. of the filtered distillate with N/10 barium hydroxide
solution. Half a grm. of silver sulphate is then added to the neutral
solution, which is frequently shaken for one hour, and filtered, and
100 c.c. of the filtrate are transferred to a distilling flask. To
this liquid are now added 35 c.c. of dilute sulphuric acid (2½ per
cent.) and a few fragments of pumice, and the whole distilled until
110 c.c. of distillate have been obtained. This is filtered, and 100
c.c. titrated with N/10 barium hydrate solution, the number of c.c.
required; calculated back to the 5 grms., giving what is termed the
“second titration value.”
According to Kirschner, the percentage of butter fat in a mixture of
butter and cocoanut oil may be calculated from the formula:—Percentage
of butter fat = 4·319 S - 0·456 R - 2·15, where S = the second
titration value, and R = the Reichert-Meissl figure. A similar formula
is given for the percentage of cocoanut oil, which = 7·42 R - 8·116 S
- 3·57. Wijsman and Reijst’s method, or the “_silver value_ method,”
is performed by treating with silver nitrate (1) the Reichert-Wollny
distillate; and (2) 250 c.c. filtered from 300 c.c. of distillate
obtained from a further 5 grms. of fat, this being saponified, treated
with acid, and 100 c.c. distilled off in the usual way, after which
100 c.c. more water are added from a tap funnel, and another 100 c.c.
distillate collected, this being once more repeated.
In both cases the filtered solutions are neutralised with N/10 alkali,
and 40 c.c. of N/10 silver nitrate solution added, the precipitated
silver salt collected on a filter and washed until about 200 to 300
c.c. of filtrate have been collected, after which 50 c.c. of N/10
sodium chloride solution is added and the excess of chloride titrated
back with N/10 silver nitrate solution, potassium chromate being used
as indicator.
Eleven-tenths of the number of c.c. required in the first case, and
six-fifths of that used in the second, give what are termed the first
and second “silver values.”
In the case of pure butter all the caprylic acid should distil over in
the first 110 c.c. so that the “second silver value” should not exceed
the first, but with cocoanut oil the distillation of caprylic acid
continues with the second and third 100 c.c. of distillate, so that the
second silver value is greater than the first. The process has been
adversely criticised by Jean (_Ann. de Chim. Anal._, 1906, ii. 121-124).
A useful qualitative test for the detection of even small quantities
of cocoanut oil in butter is that due to Hinks (_Analyst_, 1907, 160).
In this, 5 c.c. of the melted and filtered fat are dissolved in 10
c.c. of ether, and cooled to 0° C. for thirty minutes. The solidified
glycerides are then rapidly filtered off, the filtrate evaporated, and
the residue redissolved in 3 to 4 times its volume of boiling 96 to 97
per cent. alcohol. This is allowed to cool to the ordinary temperature,
and then placed in a water-bath at 5° C., at which temperature it is
kept for fifteen minutes. The alcoholic layer is filtered off into
a tube cooled to 0° C., and the flocculent precipitate, which soon
separates, is examined microscopically with a magnification of 250-300.
Butter treated in this manner deposits round, granular masses, whereas
cocoanut oil gives fine needle-shaped crystals. As little as 5 per
cent. cocoanut oil may be detected by this process.
Ross (_Analyst_, 1908, 457) has attempted to make this process
quantitative by determining the refraction of the residues obtained,
but without success.
Palm oil in butter may be detected by the Liebermann-Storch reaction
for rosin. Ten c.c. of the filtered fat are dissolved in 10 c.c. of
acetic anhydride, and 1 drop of sulphuric acid (sp. gr. 1·53) added.
The mixture is shaken, and, on standing, a blue liquid, having a
greenish tint, separates, if palm oil is present.
=Soluble and Insoluble Fatty Acids—the Hehner value.=—A weighed
quantity of about 5 grms. of the filtered butter fat is introduced
into a strong 6 oz. bottle, and 50 c.c. of approximately N/2 alcoholic
potassium hydroxide solution added, another 50 c.c. being also
placed in an empty flask. The bottle is fitted with an india-rubber
stopper, which is secured by wire, and is placed in a water-bath, being
occasionally removed, and well agitated without bringing the liquid in
contact with the stopper. After about thirty minutes, saponification
is complete (this being shown by the contents of the bottle being
free from oily globules), and the bottle is withdrawn and allowed to
cool. The stopper is then removed, and the contents of the bottle
transferred, by rinsing with boiling water, into a 10 oz. flask, which
is placed, together with the flask containing only alcoholic potassium
hydroxide solution, on a steam-bath.
As soon as all the alcohol has evaporated the contents of each flask
are neutralised with N/2 hydrochloric acid, an excess of about 1
c.c. of acid being added, and a note made of the quantity used. The
flask containing the butter fat is nearly filled with boiling water,
and placed on the water-bath, a cork with a long upright tube being
inserted. When the fatty acids have melted to a clear liquid on the
surface of the water, the flask is removed and its contents allowed to
become perfectly cold, when the fatty acids should solidify. By gently
tapping the sides of the flask this cake is detached, and the liquid is
poured through a filter into a large flask. This liquid should have a
distinct odour of butyric acid, especially on warming.
The flask containing the insoluble fatty acids is again filled with
boiling water, the cork and reflux tube inserted, and the liquid
gently heated to the boiling-point, after which the flask is removed
and thoroughly shaken until the melted fatty acids are emulsified with
the water. The fatty acids are now allowed to separate again on the
surface, solidified by cooling, detached by gently tapping, and the
liquid filtered off as before. The process is repeated three times, or
until the washings collected separately do not require more than 0·2
c.c. of N/10 sodium hydroxide solution for neutralisation.
The mixed washings are next diluted to one litre or other convenient
volume, and an aliquot part titrated with N/10 sodium hydroxide
solution, the number of c.c. required being calculated upon the whole
liquid. This amount of alkali is that required to neutralise the excess
of acid added after saponification, together with the soluble fatty
acids, and the former may be known by titrating the excess in the blank
experiment, so that the difference between these two titrations gives
the alkali absorbed by the volatile fatty acids. These are usually
expressed as butyric acid, C₃H₇COOH, the percentage of which may be
found by multiplying the number of c.c. of alkali solution required to
neutralise the soluble fatty acids by 0·0088 and by 100, and dividing
by the weight of fat taken.
_The Insoluble Fatty Acids_ are determined by allowing the flask
containing the solid cake to drain as completely as possible, melting
the fatty acids, and pouring them on to the wet filter through which
the solution of soluble fatty acids was passed. They are then washed
on the filter with boiling water, and the funnel filter transferred to
a small beaker and placed in the water-bath until all the fatty acids
have filtered through. Flask, funnel, and filter paper are well washed
with ether, the washings added to the filtered fatty acids, and the
ether evaporated. The fatty acids are then dried in the oven at 100° C.
until constant in weight, and from the weight obtained the percentage
of insoluble fatty acids is calculated on the weight of butter fat
taken. This is known as the Hehner value.
Butter should contain at least 5 per cent. of soluble fatty acids
calculated as butyric acid, and the insoluble fatty acids should not
exceed 89½, rarely 88½ per cent.
The following table contains results obtained by Thorpe (_Journ. Chem.
Soc._, 1904, 254) on 357 samples of British butters:—
LEGEND:
(A) = Reichert-Meissl-Wollny Number.
(B) = Saponification Equivalent.
(C) = Refactometer Number at 45° C.
(D) = Soluble Acids per cent. on Fat.
(E) = Insoluble Acids per cent. on Fat.
(F) = Mean Molecular Weight of Insoluble Acids.
+----------+------+----------+-------+------+-----+------+-------+
| | | Specific | | | | | |
| Number | | Gravity | | | | | |
| of | (A) | at | (B) | (C) | (D) | (E) | (F) |
| Samples. | | 37·8° C. | | | | | |
+----------+------+----------+-------+------+-----+------+-------+
| 7 | 22·5 | 0·9101 | 255·4 | 42·0 | 4·3 | 90·1 | 266·9 |
| 17 | 23·5 | 0·9104 | 253·4 | 41·5 | 4·5 | 89·7 | 265·5 |
| 15 | 24·5 | 0·9108 | 251·3 | 41·5 | 4·7 | 89·4 | 265·0 |
| 27 | 25·5 | 0·9110 | 251·1 | 41·3 | 4·8 | 89·3 | 264·2 |
| 37 | 26·5 | 0·9113 | 248·9 | 41.0 | 4·9 | 88·9 | 261·9 |
| 51 | 27·5 | 0·9114 | 247·4 | 40·6 | 5·2 | 88·7 | 261·7 |
| 78 | 28·8 | 0·9118 | 245·7 | 40·1 | 5·4 | 88·4 | 260·9 |
| 56 | 29·5 | 0·9120 | 244·0 | 40·1 | 5·6 | 88·3 | 259·6 |
| 41 | 30·5 | 0·9123 | 242·4 | 39·9 | 5·8 | 87·9 | 260·1 |
| 18 | 31·3 | 0·9125 | 241·5 | 39·7 | 5·7 | 87·9 | 258·0 |
| 10 | 32·6 | 0·9130 | 241·2 | 39·4 | 6·0 | 87·7 | 257·8 |
| | | | | | | | |
| 357 | | | | | | | |
+----------+------+----------+-------+------+-----+------+-------+
=Casein (Curd).=—This may be estimated by transferring the dry butter
used in determining the water to a dry filter of known weight, washing
it thoroughly with ether or petroleum spirit until free from fat, and
weighing the filter after drying at 100° C. The residue includes casein
and salt, and the latter may be determined as described below, and
subtracted from the total residue.
The amount of casein does not usually exceed 1 to 2 per cent., but
cases are recorded when adulteration with casein has been practised,
and as much as 5 to 6 per cent. found.
=Salt.=—For most practical purposes, the ash remaining after burning
either the dried butter, or the residue insoluble in ether, may be
taken as salt (sodium chloride). If desired, the sodium chloride may be
estimated by extracting the butter with 10 to 20 c.c. of hot water in a
separating funnel, separating the aqueous layer, repeating this about
ten to fifteen times, and titrating the aqueous washings with standard
silver nitrate solution, using potassium chromate as indicator.
The proportion of salt may vary from 0·5 for a fresh butter up to 11
per cent. for a salt butter, but should not go beyond the latter limit
(see also p. 41).
=Colouring Matters.=—The natural colouring matter of butter, which
is termed “lactochrome,” is insoluble in alcohol or glacial acetic
acid, so that if on shaking the sample with either of these reagents
a coloured extract is obtained, artificial colouring matter has
undoubtedly been added.
Two general schemes have been devised for the detection of artificial
colouring matters in butter or margarine: (1) devised by Leeds
(_Analyst_, 1887, 150), in which the fat and colouring matter are first
extracted with petroleum ether, and the colouring matter dissolved
out of the ethereal extract with N/10 potassium hydroxide, and
reprecipitated with dilute hydrochloric acid; and (2) that devised by
Cornelison (_Journ. Amer. Chem. Soc._, 1908, 1478), who extracts the
colouring matter directly by means of glacial acetic acid.
--------------+-------------+--------------+------------+------------
|Concentrated |Concentrated | Sulphuric |Concentrated
Colouring | Sulphuric | Nitric Acid. | Acid and |Hydrochloric
Matter. | Acid. | |Nitric Acid.| Acid.
--------------+-------------+--------------+------------+-------------
Annatto |Indigo blue |Blue becoming |Same. |No change, or
| changing to | colourless | | only slight
| violet. | on standing. | | dirty yellow
| | | | and brown.
Annatto and |Blue becoming|Blue through |Decolorised.|No change, or
decolorised | green | green and | | only slight
butter. | and slowly | bleached. | | dirty
| changing to | | | yellow.
| violet. | | |
Turmeric |Pure violet. |Violet. |Violet. |Violet changing
| | | | to original
| | | | colour on
| | | | evaporation
| | | | of HCl.
Turmeric and |Violet to |Violet to |Same. |Very fine
decolorised | purple. | reddish | | violet.
butter. | | violet. | |
Saffron |Violet to |Light blue |Same. |Yellow
| cobalt-blue | changing to | | changing
| changing |light reddish | | to dirty
| to reddish | brown. | | yellow.
| brown. | | |
Saffron and |Dark blue |Blue through |Blue quickly|Yellow
decolorised | changing | green to | changing to| becoming
butter. | quickly to | brown. | purple. | dirty
| reddish | | | yellow
| brown. | | |
Carrot |Umber brown. |Decolorised. |Do. with |No change.
| | | NO₂ fumes |
| | | and odour |
| | | of burnt |
| | | sugar. |
Carrot and |Reddish brown|Yellow and |Same. |Slightly
decolorised | to purple | decolorised. | | brown.
butter. | similar to | | |
| turmeric. | | |
Marigold |Dark olive |Blue changing |Green. |Green to
| green. | instantly to | | yellowish
| Permanent. | dirty yellow | | green.
| | green. | |
Safflower |Light brown. |Partially |Decolorised.|No change.
| | decolorised. | |
Aniline yellow|Yellow. |Yellow. |Yellow. |Yellow.
Martius yellow|Pale yellow. |Yellow reddish|Yellow. |Yellow
| | precipitate,| | precipitate
| | magenta at | | treated
| | margin. | | with NH₃
| | | | deflagrates.
Victoria yellow|Partially | Same. |Same. |Same colour
| decolorised.| | | returns on
| | | | neutralising
| | | | with NH₃.
--------------+-------------+--------------+------------+-------------
Leeds’ process is carried out by mixing 100 grms. of the sample with
300 c.c. light petroleum spirit (sp. gr. 0·638), separating the
ethereal layer by means of a separating funnel, and washing it with 100
c.c. of water in successive small quantities. The ethereal extract is
allowed to stand for fifteen to twenty hours surrounded by ice, and is
then decanted from any separated “stearin” and shaken with 50 c.c. of
N/10 potassium hydroxide solution. The alkaline extract is separated,
made faintly acid with dilute hydrochloric acid, and the precipitated
colouring matter filtered off, together with a trace of fatty acid,
which is always dissolved out by the alkali. The colouring matter may
then be identified by the tests given on the preceding page.
In Cornelison’s method 10 grms. of the melted fat are thoroughly shaken
with 10 to 20 grms. of glacial acetic acid, at about 35° C., the
mixture allowed to separate, and the acid liquid drawn off. The colour
of the latter is noted, and portions treated with various reagents to
identify the colouring matter. The table on p. 125 gives the results
obtained with the colouring matters mentioned, incorporated with pure
butter in the proportion of 1 part in 100,000.
PRESERVATIVES (see p. 46).
=Boron Compounds.=—The presence of these may be detected by thoroughly
mixing some of the butter with excess of water in a mortar, pouring
off the water, acidifying with a drop of dilute hydrochloric acid, and
moistening a piece of turmeric paper with the solution. The paper is
then dried in the oven, when, if boron compounds are present, the paper
develops a reddish pink tint, changing to dark blue when moistened with
weak alkali.
----------------+-------------+-------------+-------------+----------------
| | |Concentrated | Sulphuric Acid
Dye. | Colour of |Concentrated | Sulphuric | and Ether to
|Acid Extract.|Nitric Acid. | Acid. | Clear Solution.
----------------+-------------+-------------+-------------+----------------
(Pure natural |Colourless. |Colourless. |Faint pink on|Colourless.
butter) | | | standing. |
Soudan I. |Decided pink.|Strong pink. |Strong clear |Pink.
(pure) | | | pink. |
Butter yellow |Very faint |Faint pink. |Faint pink. |Faint.
(impure). | pink. | | | colour
Cerasine |Strong |Acid yellow; |As with |Brownish
orange G. | greenish | oil-globule,| HNO₃. | yellow.
(Casella). | yellow. | salmon-pink.| |
Yellow O.B. |Decided |Acid faint |As with |Pink.
(Heller | bright | pink; | HNO₃. |
and Merz). | yellow. | oil-globule,| |
| | salmon-pink.| |
Yellow A.B. |Slight warm |Pink; fat |Brownish |Pink.
(Heller |ochre-yellow.| colourless. | pink; oil |
and Merz). | | | faint pink. |
Annatto |Dull yellow. |Little |Faint pink on|Very faint
| | change. | standing. | yellow.
Curcumine |Intense |Dull |Strong pink. |Yellow.
| greenish |ochre-yellow.| |
| yellow. | | |
Carrot |Very faint |Faint yellow.|Faint pink on|Very faint
| greenish | | standing. | yellowish.
| yellow. | | |
“Alderney |Brownish |Strong pink. |Strong pink. |
butter | yellow. | | |
colour” | | | |
(Heller | | | |
and Merz). | | | |
Ranson’s |Yellow. |Almost |As with |
butter | | decolorised.| HNO₃. |
colour | | | |
(“vegetable”). | | | |
“Dandelion brand”|Yellow. |Almost |As with |
butter colour | | decolorised.| HNO₃. |
(“vegetable”). | | | |
----------------+-------------+-------------+-------------+---------
The amount of boron compound may be readily estimated by Richmond and
Harrison’s modification of Thomson’s process. Twenty-five grms. of
the sample are weighed into a 100 c.c. stoppered cylinder, and, after
determination of the moisture present, sufficient water is added to
bring the total volume of water up to such a quantity that 1 c.c.
corresponds to 1 grm. of butter. From 10 to 15 c.c. of chloroform are
now introduced, and the contents of the flask heated, shaken, and
allowed to separate. An aliquot portion of the aqueous liquid is then
removed by means of a pipette, evaporated to dryness, ignited, and the
residue extracted with hot water. The extract is made neutral to methyl
orange, boiled to expel carbon dioxide, half its volume of neutral
glycerin added, and the mixture titrated with N/10 sodium hydroxide
solution until pink to phenol-phthalein. Each c.c. of N/10 sodium
hydroxide solution is equivalent to 0·0062 grms. of boric acid.
Another method, devised by Richmond and Harrison (_Analyst_, 1902,
181), is to weigh out 25 grms. of the sample in a beaker, add 25
c.c. of a solution containing 6 grms. of milk sugar and 4 c.c. of
N/1 sulphuric acid, in 100 c.c. of water. The beaker is placed in a
water-oven until the fat has just melted, and the contents are then
stirred well, allowed to separate, and 20 c.c. of the aqueous liquor
withdrawn. A few drops of phenol-phthalein are then added, and the
liquid heated to the boiling-point, and titrated with N/2 sodium
hydroxide solution until faintly pink, after which 12 c.c. of glycerin
are added, and more N/2 sodium hydroxide solution run in until a faint
pink colour is again obtained. The amount of alkali required in the
second titration, less the alkali required to neutralise 12 c.c. of
the glycerin, multiplied by 0·0368, gives the amount of boric acid in
20 c.c. of the aqueous extract, and the percentage may be calculated
by multiplying by (100 + percentage of water in the butter), and
dividing by 20. In an average butter the number of c.c. of N/2 sodium
hydroxide solution used, multiplied by 0·2, approximates closely to the
percentage of boric acid.
The best method of testing for benzoic acid, salicylic acid, fluorides,
and [Greek: b]-naphthol is to extract the melted butter with a dilute
solution of sodium bicarbonate, and to examine this extract for the
various preservatives.
Thus, in testing for benzoic and salicylic acids, the alkaline extract
is exactly neutralised with dilute hydrochloric acid, and a solution of
ferric chloride added. If benzoic acid or a benzoate has been added,
a buff-coloured precipitate will be immediately thrown down, and if
salicylic acid has been employed, an intense violet coloration will be
produced.
Numerous methods have been suggested for detecting even very minute
admixtures of benzoic acid or benzoates, among which may be mentioned
those of Halphen (_Journ. Pharm. Chim._, 1908, 201) and Robin (_Ann. de
Chim. Anal. Appl._, 1908, 431).
Halphen’s test depends on the conversion of the benzoic acid into
ammonium diamido-benzoate, which, in alkaline solution, has a brown-red
colour. A quantity of the butter is melted with sufficient lime-water
to render the aqueous liquor which separates distinctly alkaline. After
cooling, the latter is separated, acidified with phosphoric acid, and
extracted with ether. The ether is allowed to evaporate spontaneously,
and the residue dried at the ordinary temperature, after which it
is gently heated with 2 c.c. of concentrated sulphuric acid until
completely dissolved. An addition of 0·2 c.c. of fuming nitric acid is
now made, and the solution transferred to a dry test tube and heated
carefully over a small flame until sulphuric acid fumes appear. After
cooling, the mixture is diluted with 5 or 6 c.c. of water, which causes
nitrous fumes to be evolved. When again cold, a saturated solution of
sodium sulphite is added drop by drop until all yellow vapours have
disappeared. Ammonia is then allowed to flow over the surface of the
solution, and if benzoic acid is present, an orange-red coloration is
produced, the intensity of which is proportional to the quantity of
benzoic acid. In case no coloration is produced, the absence of benzoic
acid may be confirmed by adding a drop of ammonium sulphide to the
ammoniacal solution, when, if benzoic acid is present, a red coloration
develops at the point of contact of the two liquids.
By Robin’s process it is claimed that as little as 12 parts per 100,000
of sodium benzoate may be detected with certainty. The test is carried
out by shaking 25 grms. of the melted butter with a solution of 0·4 to
0·5 grm. of sodium bicarbonate in 50 c.c. of water, and 15 c.c. of 95
per cent. alcohol, and allowing the mixture to stand for ten minutes,
after which the alcoholic layer is drawn off, acidified with 7 or 8
drops of hydrochloric acid, and heated to the boiling-point. It is then
shaken with a little talc, and filtered, the cold filtrate extracted
in a separating funnel with 40 c.c. of ether, and the ethereal extract
washed once with a mixture of 20 c.c. of water, 5 c.c. of 95 per cent.
alcohol, and 0·2 to 0·3 grm. of sodium bicarbonate. The alkaline
alcoholic extract is evaporated on the water-bath, and the residue
carefully warmed with a mixture of 5 c.c. of concentrated sulphuric
acid and 10 drops of fuming nitric acid, until white fumes appear,
after which the liquid is poured into 50 c.c. of water containing
a small piece of turmeric paper. A yellow coloration indicates the
presence of benzoic acid, which may be confirmed by adding ammonia
solution until alkaline, then a few drops of ammonium sulphide
solution, and shaking the vessel. In the presence of benzoic acid the
colour changes from yellow to reddish orange.
=Fluorides.=—The presence of these may be detected in the absence of
boric acid by evaporating a small quantity of the alkaline extract
to dryness in a platinum crucible, igniting the residue, moistening
it with a few drops of concentrated sulphuric acid, and covering the
mouth of the crucible with a piece of glass, coated with paraffin wax,
through which some marks have been scratched.
Fluorides may also be detected by applying the above process to the
aqueous liquor, which separates when a sample of the butter is melted.
If boric acid is present, the fluoride is liable to be lost by
volatilisation as boron fluoride. It is necessary, therefore, to
separate the borate as calcium borate, by rendering the liquid alkaline
with lime-water, evaporating it to dryness, and extracting the residue
with dilute acetic acid, which dissolves calcium borate. The insoluble
matter is then dried, and treated with concentrated sulphuric acid as
described above.
MARGARINE, VEGETABLE BUTTER, OR OTHER BUTTER SUBSTITUTES
The analysis of these is a matter requiring a considerable amount of
skill, and even when the analysis is made, very long experience is
necessary before a right interpretation can be put upon the chemical
and physical data obtained.
The only requirements for margarine under the Sale of Food and Drugs
Act, 1899, are that the sample shall not contain more than 16 per cent.
water or more than 10 per cent. of butter. The same restrictions as to
preservatives apply to this as to genuine butter.
The amount of water is readily determined by the method given under
“Butter” (p. 109). The method officially adopted by the Committee of
the Society of Public Analysts for the estimation of butter is the
Reichert-Meissl-Wollny process (p. 111), the maximum permissible limit
for the Reichert-Wollny value being 4, and a Reichert-Wollny value of
7·1 being regarded as indicative of the presence of 20 per cent. butter
fat.
In addition to the analysis of margarine to ensure compliance with
these standards, it is often desirable to endeavour to determine the
precise composition of a sample of artificial butter, such as the
relative proportions of animal and vegetable fats, and the particular
fats or oils of which they consist. It is here where only prolonged
experience can decide what tests to apply and determine the correct
interpretation to put upon the results obtained.
In an exhaustive analysis, the specific gravity, saponification value,
iodine value, titre, and Reichert-Wollny-Polenské figures should always
be determined, and such qualitative tests as Halphen’s for cotton-seed,
Baudouin’s for sesame, the arachidic acid test for arachis oil, and the
Liebermann-Storch test for palm oil applied.
The tests for colouring matters and preservatives are the same as for
natural butter.
LARD
In addition to the tests mentioned in Chapter V. pp. 60 _et seq._,
Halphen’s test for cotton-seed oil and Baudouin’s test for sesame oil
should be applied, and, if thought desirable, arachis oil may be tested
for by the arachidic acid method. The presence of as little as 2 to 3
per cent. cotton-seed oil may be detected by the phytosteryl acetate
test (see p. 101), and the addition of maize oil, which is sometimes
used for adulterating lard, will also be shown by the same method.
Preservatives may be detected, and, if present, estimated as described
under “Butter.”
CHEESE
The composition of cheese is so variable that it is to be regretted
there are no standards to which it should conform.
The proportion of fat may vary from 20 per cent. or less to 35 or 40
per cent., or, in a cream cheese, up to 75 per cent., while the water
may be anything between 20 and 40 per cent.
The analysis of cheese should include determinations of the proportions
of water, ash, fat, and nitrogen, and an examination of the fatty
matter.
_Water._—This may be determined by drying a weighed quantity of about 5
grms. of the sample, cut in thin slices, in the oven at 105° C., until
constant in weight.
_Ash._—The dried cheese, as obtained in the above determination, is
ignited at as low a temperature as possible, and the residue weighed
when the whole of the carbon has been burned away.
_Fat._—This may be determined approximately by grinding up 25 to 50
grms. of the dried cheese with ignited sand, and extracting the mixture
in a Soxhlet apparatus with ether or petroleum spirit, the extract
being collected in a weighed carbonic acid flask, from which the
solvent is afterwards distilled off, and the residue dried in the oven
at 105° C., and weighed.
A better method is that of Palmquist, which is a modification of the
Rose-Gottlieb process. In this, about 1 grm. of the cheese is weighed
into a Gottlieb tube, 10 c.c. of 2·5 per cent. ammonia solution added,
and the mixture warmed on the water-bath, and shaken until a milky
homogeneous solution is obtained. After cooling, 10 c.c. alcohol and 25
c.c. of ether are added, the tube being thoroughly shaken after each
addition. An addition of 25 c.c. of petroleum spirit is then made, and
the tube, after being again well shaken and inverted, is allowed to
stand for a few hours for its contents to separate, after which the
ethereal layer is siphoned into a weighed flask. A second extraction
of the mass remaining in the tube is then carried out in an exactly
similar manner, the ethereal extract being again siphoned into the
weighed flask, the solvent distilled off, and the residue dried in the
oven at 105° C., and weighed.
A larger quantity of the fat for its examination may be readily
prepared by cutting up a quantity of the cheese, wrapping it in a
piece of muslin, and suspending over a basin in an oven at 105° C. The
clear fat collected should then be examined, and its Reichert-Wollny
value, which should be similar to that of butter, determined. If the
Reichert-Meissl-Wollny figure is abnormal, the fat requires further
systematic examination by the processes mentioned under “Margarine” (p.
130), to detect foreign fats.
_Nitrogen._—This is estimated by heating 1 to 2 grms. of the cheese
with concentrated sulphuric acid and a globule of mercury, as in
the well-known Kjeldahl process. The proteins may be calculated by
multiplying the percentage of nitrogen by 6·3.
CHOCOLATE
No standards have yet been legally fixed in this country for any of
the various forms of chocolate, though such standards are in existence
on the Continent, and are urgently needed in view of the large amount
of adulteration practised in this industry. Not only is the natural
fat of the chocolate replaced by other fats, such as cocoanut oil, and
cocoanut stearin, or palm-nut stearin, and the chocolate adulterated
with excessive husk or starch, but products are sold as milk or cream
chocolate which have no right to such designations. Hence N. P. Booth
presented to the International Congress of Applied Chemistry, held in
London last year, the following proposed standards, which are not more
stringent than those adopted by some Continental countries and by some
of the Colonies:—
1. _Unsweetened Chocolate_ must be prepared exclusively from roasted,
shelled, finely ground cocoa-beans, with or without the addition of a
small quantity of flavouring matter. It should contain not less than 45
per cent. of cacao butter.
2. _Sweetened Chocolate._—A preparation consisting exclusively of
the products of roasted, shelled, finely ground cocoa-beans, and not
more than 65 per cent. of sugar, with or without a small quantity of
harmless flavouring matter.
3. _Granulated or Ground Chocolate for Drinking Purposes._—The same
definition as for sweetened chocolate should apply here, except that
the proportion of sugar may be raised to not more than 75 per cent.
4. _Chocolate-covered Goods._—Various forms of confectionery covered
with chocolate, the composition of the latter agreeing with the
definition of a sweetened chocolate.
5. _Milk Chocolate._—A preparation composed exclusively of roasted,
shelled cocoa-beans, sugar, and not less than 15 per cent. of the dry
solids of full-cream milk, with or without a small quantity of harmless
flavouring matter.
The analysis of chocolate should comprise determinations of the
moisture, ash, fat, fibre, total nitrogen, and sugar, and an
examination of the nature of the fatty matter and sugar.
In the case of milk chocolate or cream chocolate, the fatty matter
should contain both cacao butter and butter fat, and the sugar should
contain lactose.
The analysis is carried out as follows:—
_Water._—A weighed quantity of about 5 grms. is finely divided, and
dried in the oven at 105° C., until constant in weight.
_Ash._—The dried product obtained in the determination of the moisture
is cautiously burnt until all carbonaceous matter is volatilised. The
proportion of ash should not exceed 1 to 1·5 per cent., unless the
sample has been coloured with mineral colouring matter, such as ochre.
_Fat._—This may be estimated by extracting 5 grms. of the finely ground
sample in an extraction thimble with ether or light petroleum spirit,
by means of a Soxhlet apparatus. The extracting liquid is collected in
a small weighed flask, which, when extraction is complete, is detached
from the Soxhlet apparatus, the solvent distilled off, and the residual
fat weighed, after being dried in the oven at 105° C.
Kreutz (_Zeit. Untersuch. Nahr. Genussm._, 1908, 584-586) recommends
melting the sample with chloral alcoholate prior to extraction with
ether. From 2 to 3 grms. of the chocolate are placed in a small flask
with 3 to 4 grms. chloral alcoholate, and the mixture melted by heating
on a water-bath. The hot mass is well stirred with 10 to 15 c.c. of
ether, a further 35 c.c. of ether added, and, after thorough shaking,
the mixture is filtered through a dry filter. The filtrate is passed
through the filter again and again until perfectly bright, and the
residue on the filter washed with ether three times. The ether is
then distilled off, and any chloral alcoholate removed by heating the
residue to about 75° C., under reduced pressure. The residue obtained
is extracted with carbon tetrachloride and filtered to eliminate a
little theobromine and colouring matter, the filtrate evaporated in a
weighed flask, and the residue of fat dried in the oven at 105° C., and
weighed.
For the examination of the fat a larger quantity may be prepared by
simply shaking up about 15 to 20 grms. of the finely ground sample
in a stoppered bottle with three or four successive quantities of
petroleum spirit, allowing the mass to settle, pouring off the
solvent, and evaporating it. The residual fat should then be examined
for its refractive power, its Reichert-Meissl-Polenské values, its
saponification value, its iodine value, and its titre.
Genuine cacao butter gives a refractometer reading at 35° C. of about
49°, has a Reichert-Meissl value of 1 or rather less, a saponification
value of about 286-290, an iodine value of about 34, and a titre of
about 48° C. Cocoanut oil has a refractive power of only about 37°,
and is thus readily detected by this, as also by the much increased
saponification value and reduced iodine value, and the increased
Reichert-Meissl figure.
Cocoanut stearin also increases the saponification value, reduces the
iodine value, and raises the Reichert-Meissl figure. Palm-nut stearin
increases the saponification value, reduces the iodine number, and
slightly raises the Reichert-Meissl figure, its own Reichert-Meissl
value being about 2·2.
Of the other fats said to be used as substitutes for cacao butter, and
mentioned in Chapter VII.
_Dika, or Gaboon Fat_, raises the saponification value, lowers the
iodine value, but does not affect the Reichert-Meissl figure.
_Borneo Tallow, or Tankawang Fat_, has analytical values very similar
to those of cacao butter.
_Illipé Fat_ has a much higher iodine value (54-60). (See also p. 87.)
_Fibre._—This is best estimated by Allen’s method (_Commercial Organic
Analysis_, iii., Part II., p. 567), in which 2 grms. are freed from
fat, and boiled for thirty minutes under a reflux condenser with 200
c.c. of water and 2½ c.c. of sulphuric acid. The liquid is filtered
through linen, and the residue thoroughly washed with hot water and
boiled with 200 c.c. of 1¼ per cent. solution of sodium hydroxide. The
residue is filtered off, washed with hot water, alcohol, and ether,
and dried at 110° C., and weighed. It is then ignited, and the loss
regarded as crude fibre.
_Total Nitrogen._—This is estimated on about 2 grms. of chocolate by
the Kjeldahl method. In an ordinary chocolate it is normally about
1 per cent., and in a milk chocolate slightly higher. In a plain
chocolate the proportion of nitrogen, multiplied by 20, will give the
percentage of fat-free cocoa.
_Sugar._—This may be determined in plain chocolate by means of a
polarimeter, a 20 per cent. aqueous solution, which is clarified with
lead acetate in the ordinary way, being used. In the case of milk
chocolate the introduction of lactose complicates the determination
slightly, but estimation of the copper-reducing power enables the
lactose to be calculated, and an allowance made for its effect on the
optical rotation.
[Illustration: FIG. 2.]
CHAPTER IX
STATISTICS OF THE TRADE IN EDIBLE OILS
In basing any conclusions as to the consumption of edible oils upon the
figures published by the Customs authorities of different countries,
allowance must be made for the fact that in many cases (_e.g._ seed
oils) it is not possible to distinguish the quantities used for food
from those used for soap and lubricating purposes.
=United Kingdom Trade.=—The following figures are taken from the tables
published annually by the Board of Trade, and show the import of oils
during the ten years ending 1908:—
+-----------------+--------------+--------------+--------------+
| Oils. | 1899. | 1900. | 1901. |
+-----------------+--------------+--------------+--------------+
|Cocoanut, cwts. | 458,297 | 552,743 | 478,143 |
|Olive, tuns | 15,939 | 12,044 | 15,488 |
|Palm, cwts. | 945,472 | 938,350 | 1,212,111 |
|Seed oils, tuns | 46,416 | 41,131 | 48,842 |
+-----------------+--------------+--------------+--------------+
| Oils. | 1902. | 1903. |
+-----------------+--------------+--------------+
|Cocoanut, cwts. | 495,860 | 782,632 |
|Olive, tuns | 18,978 | 14,485 |
|Palm, cwts. | 1,446,298 | 1,234,004 |
|Seed oils, tuns | 35,454 | 36,011 |
+-----------------+--------------+--------------+
+-----------------+--------------+--------------+--------------+
| Oils. | 1904. | 1905. | 1906. |
+-----------------+--------------+--------------+--------------+
|Cocoanut, cwts. | 615,238 | 613,165 | 335,545 |
|Olive, tuns | 15,101 | 7,690[1] | 9,419[1] |
|Palm, cwts. | 1,309,176 | 1,144,368 | 1,223,787 |
|Seed oils, tuns | 10,553 | 3,309[1] | 1,786[1] |
+-----------------+--------------+--------------+--------------+
| Oils. | 1907. | 1908. |
+-----------------+--------------+--------------+
|Cocoanut, cwts. | 335,781 | 555,335 |
|Olive, tuns | 7,391[1] | 6,330[1] |
|Palm, cwts. | 1,508,023 | 1,317,995 |
|Seed oils, tuns | 1,111[1] | 2,203[1] |
+-----------------+--------------+--------------+
[Footnote 1: Not including refined oil.]
The amounts of the chief edible oils and their value imported into
this country during the three years ending 1909 were as follows:—
_Imports_
+------------------------+-----------+-----------+-------------+
| Oil. | 1907. | 1908. | 1909. |
+------------------------+-----------+-----------+-------------+
| _Crude_— | | | |
|Cocoanut, cwts. | 357,815 | 555,335 | 502,408 |
|Olive, tuns | 7,391 | 6,330 | 4,788 |
|Palm, cwts. | 1,508,023 | 1,317,995 | 1,762,641 |
| | | | |
| _Refined_— | | | |
|Cocoanut, cwts. | 118,903 | 203,077 | 177,085 |
|Cotton-seed, tuns | 14,226 | 15,251 | 17,560 |
|Olive, tuns | 4,937 | 5,822 | 4,186 |
|Palm, cwts. | 18,656 | 35,838 | 58,645 |
+------------------------+-----------+-----------+-------------+
|Butter, cwts. | 4,210,156 | 4,210,821 | 4,062,833 |
|Margarine, cwts. | 885,068 | 813,447 | 868,292 |
+------------------------+-----------+------------+------------+
|Lard from U.S.A., cwts. | 1,903,961 | 1,924,881 | 1,703,578 |
|Lard from other | | | |
| countries, cwts. | 61,170 | 62,610 | 56,707 |
+------------------------+-----------+------------+------------+
|Imitation lard, cwts. | 222,090 | 174,064 | 231,847 |
+------------------------+-----------+------------+------------+
| Oil. | 1907. | 1908. | 1909. |
+------------------------+-----------+------------+------------+
| _Crude_— | £ | £ | £ |
|Cocoanut, cwts. | 634,357 | 757,812 | 752,257 |
|Olive, tuns | 287,254 | 243,497 | 241,905 |
|Palm, cwts. | 1,896,133 | 1,559,266 | 2,195,620 |
| | | | |
| _Refined_— | | | |
|Cocoanut, cwts. | 223,522 | 323,334 | 315,690 |
|Cotton-seed, tuns | 365,512 | 401,506 | 482,139 |
|Olive, tuns | | | |
|Palm, cwts. | 251,634 | 293,308 | 276,743 |
+------------------------+-----------+------------+------------+
|Butter, cwts. |22,417,926 | 24,080,912 | 22,425,067 |
|Margarine, cwts. | 2,223,645 | 2,081,245 | 2,243,737 |
+------------------------+-----------+------------+------------+
|Lard from U.S.A., cwts. | | | |
|Lard from other | 4,491,539 | 4,407,410 | 4,857,199 |
| countries, cwts. | | | |
+------------------------+-----------+------------+------------+
|Imitation lard, cwts. | 408,192 | 306,700 | 438,909 |
+------------------------+-----------+------------+------------+
_Exports_
+---------------------+------+------+------+-------+-------+--------+
| Oil, etc. | 1907.| 1908.| 1909.| 1907. | 1908. | 1909. |
+---------------------+------+------+------+-------+-------+--------+
| _Crude_— | | | | £ | £ | £ |
|Cocoanut, cwts.|56,058|56,887|61,247| 95,074| 79,563| 89,327 |
|Olive, tuns | | 26| 70| | 1,341| 3,915 |
|Palm, cwts.| 4,946| 415| 1,787| 7,568| 543| 2,554 |
| _Refined_, | | | |846,037|705,020|822,923 |
|Butter, cwts.|12,305|10,045| 9,214| 68,591| 59,324| 54,825 |
|Lard, cwts.| 9,634| 8,118| 5,506| 26,340| 22,340| 18,722 |
|Imitation lard, cwts.| 568| 583| 792| 1,000| 1,008| 1,604 |
+---------------------+------+------+------+-------+-------+--------+
In the case of the crude oils mentioned in the above tables it is
probable that the bulk was used for technical purposes.
=Olive Oil.=—Large quantities of foreign olive oil are imported into
the French Riviera, the bulk coming from Italy and Tunis, and a small
proportion from Spain, Turkey, Algiers, and Greece.
According to statistics published by Slaus-Kantschlieder (_Chem. Rev.
Fett- u. Harz-Ind._, 1909, xvi. 223-231), the importations into Nice
amounted to 8,264,900 kilos in 1907, as compared with 11,917,200 kilos
in 1906.
The quantities of olive oil exported from Nice to various countries
during the two years were as follows:—
+----------------+---------+---------+
| Exported to— | 1906. | 1907. |
+----------------+---------+---------+
| | Kilos. | Kilos. |
|Austria-Hungary | 351,000 | 370,000 |
|Germany | 748,000 | 749,000 |
|Russia | 436,000 | 624,000 |
|England | 234,000 | 206,000 |
|Switzerland | 313,000 | 289,000 |
|Roumania | 70,000 | 123,000 |
|Servia | 14,000 | 21,000 |
|Bulgaria | 4,600 | 5,200 |
+----------------+---------+---------+
=Italian Trade in Olive Oil.=—The Italian Customs authorities give
the following details of the exports of refined and other grades of
olive oil during the three years ending 1907, the quantities being in
quintals (1 quintal = 220·46 lb.):—
_Refined Olive Oil_
+----------------+------------+------------+----------+
| Exported to— | 1907. | 1906. | 1905. |
+----------------+------------+------------+----------+
| | Quintals. | Quintals. | Quintals.|
|United States | 29,188 | 71,400 | 38,687 |
|Austria-Hungary | 28,998 | 22,203 | 7,752 |
|Germany | 15,690 | 11,132 | 5,490 |
|Great Britain | 5,861 | 9,432 | 4,102 |
|Holland | 12,648 | 73,519 | 8,403 |
|Switzerland | 7,626 | 11,294 | 6,936 |
|Egypt | 15,353 | 19,285 | 4,867 |
|Other countries | 8,536 | 8,894 | 4,900 |
+----------------+------------+------------+----------+
| Totals | 123,900 | 227,159 | 81,137 |
+----------------+------------+------------+----------+
| Total values | $1,471,122 | $2,051,652 | $945,600 |
+----------------+------------+------------+----------+
_Other Grades of Olive Oil_
+---------------------+-------------+-------------+------------+
| Exported to— | 1907. | 1906. | 1905. |
+---------------------+-------------+-------------+------------+
| | Quintals. | Quintals. | Quintals. |
|Austria-Hungary | 19,013 | 25,834 | 18,293 |
|France | 60,766 | 116,312 | 43,191 |
|Germany | 17,793 | 21,222 | 11,058 |
|Great Britain | 25,000 | 29,739 | 22,184 |
|Russia | 26,677 | 22,854 | 29,765 |
|Switzerland | 7,124 | 8,819 | 5,668 |
|Egypt | 2,636 | 5,810 | 1,956 |
|United States | 82,198 | 95,258 | 52,577 |
|Brazil | 14,495 | 12,320 | 8,820 |
|Argentina | 90,347 | 109,194 | 58,256 |
|Uruguay | 9,402 | 8,190 | 3,893 |
|Other countries | 32,976 | 33,032 | 17,440 |
+---------------------+-------------+-------------+------------+
| Totals | 388,427 | 488,584 | 273,101 |
+---------------------+-------------+-------------+------------+
| Total Values | $9,370,801 | $11,787,041 | $6,852,104 |
+---------------------+-------------+-------------+------------+
| Grand Totals | 512,327 | 715,743 | 354,238 |
+---------------------+-------------+-------------+------------+
| Grand Total Values | $10,861,923 | $13,838,693 | $7,797,704 |
+---------------------+-------------+-------------+------------+
=Spanish Oil Trade.=—Some interesting details of the production of
olive oil in Spain were given in the _Board of Trade Journal_ for
September 1907. The average output of the oil was estimated at 200,000
metric tons. In 1906 it amounted to 133,665 tons (metric), as against
149,249 tons in 1905. The deficiency in the crop of 1906 accounted for
the falling off of the exports of oil in that year, though owing to the
official pecuniary encouragement given to the manufacture of seed oils
in Spain, there was not a corresponding increase in the importations of
oils employed as substitutes for olive oil.
The imports of seed oils, cocoanut, and palm-nut oils and oil seeds
into Spain, and the exports of olive oil during the years 1905 and
1906, and the first six months of 1907, were as follows:—
_Spanish Oil Trade_
+-----------------------+--------------+--------------+------------+
| | | | First |
| | 1905. | 1906. | six months |
| | | | of 1907. |
+-----------------------+--------------+--------------+------------+
|_Imports_:— | Metric tons. | Metric tons. |Metric tons.|
| Seed oil | 684 | 895 | 330 |
| Cocoanut and palm-nut| 279 | 548 | 400 |
| oil | | | |
| Oil seeds | 39,526 | 45,233 | 32,917 |
|_Export_:— | | | |
| Olive oil | 34,228 | 18,911 | 6,150 |
+-----------------------+--------------+--------------+------------+
=Vegetable Oil Trade in France.=—The following details of the trade of
France in vegetable oils are given by the _Oil, Paint, and Drug Rep._,
April 4, 1910:—
During 1909, 141,080 metric tons of copra (cocoanut pulp) were imported
into France as against 169,357 tons in 1908, and 110,008 tons in 1907,
nearly the whole of the quantity going to Marseilles.
About 40 per cent. of the imports were from the Philippines, 29 per
cent. from the Dutch Indies, 9 per cent. from British India, 8 per
cent. from Mauritius, and the remainder from other countries.
The total values of oil products used in France in 1909 were officially
estimated at £2,044,500, including—Arachis nuts, £4,511,000; linseed,
£1,999,800; sesame seed, £892,000; mustard and Indian rape seed,
£864,000; poppy seed, £399,800; and cotton-seed (chiefly Egyptian),
£262,000.
The following figures show the imports of oil seeds into Marseilles
during the three years:—
+------------------------+---------+---------+---------+
| | 1907. | 1908. | 1909. |
+------------------------+---------+---------+---------+
| | Tons. | Tons. | Tons. |
|Sesame | 68,836 | 41,749 | 64,087 |
|Arachis nuts, shelled | 113,219 | 85,653 | 170,012 |
| ” ” unshelled | 123,304 | 102,188 | 155,056 |
|Linseed | 21,202 | 17,085 | 16,962 |
|Rape and ravison | 5,082 | 2,202 | 5,795 |
|Poppy seed | 4,106 | 2,334 | 2,356 |
|Castor seed | 16,370 | 18,111 | 11,553 |
|Pulghere | 520 | 709 | 1,818 |
|Cotton-seed | 15,884 | 14,497 | 14,249 |
|Niger and kapok | 6,351 | 3,701 | 5,118 |
|Copra | 109,744 | 163,999 | 136,655 |
|Palm kernels | 4,412 | 1,675 | 3,639 |
|Mowhrah, illipé, etc. | 12,781 | 11,146 | 8,856 |
+------------------------+---------+---------+---------+
| Totals | 501,811 | 465,049 | 596,156 |
+------------------------+---------+---------+---------+
The only oils imported in any quantities were cotton-seed, olive, and
palm oils, the average importations of which during the last five years
were:—
Tons.
Cotton-seed oil 24,000
Olive oil 22,000
Palm oil 16,000
The copra imported is chiefly used in the manufacture of soap, though
about a third is manufactured into edible cocoanut oil and vegetable
butters.
The cocoanut oil exported from Marseilles (chiefly to England, the
United States, Switzerland, and Austria) amounted to 23,840 tons in
1909, while 22,726 tons were sent from Marseilles to other parts of
France.
=Cotton-Seed Oil in the United States.=—The growth of the now gigantic
cotton-seed oil industry in the United States is illustrated by the
following figures given by the _Oil, Paint, and Drug Rep._, June 7,
1909, which show the production and exports of the seed and its product
since 1872:—
_Production of Cotton-Seed and Oil_
+------------+---------------------------+-------------+-----------+
| | Cotton-seed. | | Cake and |
|Year ending +-----------+---------------+ Oil | Meal |
| June 30. | Produced. | Manufactured. | Produced. | Produced.|
+------------+-----------+---------------+-------------+-----------+
| | Tons. | Tons. | Gallons. | Tons. |
| 1909 | 5,903,838 | 3,669,747 | 146,789,880 | 1,491,752 |
| 1908 | 4,952,402 | 2,564,873 | 103,049,820 | 1,043,080 |
| 1907 | 5,912,646 | 3,843,981 | 153,759,240 | 1,785,804 |
| 1906 | 5,060,205 | 3,131,175 | 125,700,928 | 1,271,740 |
| 1904 | 4,716,591 | 3,241,426 | 121,877,618 | 1,155,568 |
| 1902 | 4,630,311 | 3,154,417 | 118,606,079 | 1,124,550 |
| 1900 | 4,668,346 | 2,479,386 | 93,325,729 | 884,391 |
| 1890 | 3,494,811 | 873,702 | 34,948,000 | 305,800 |
| 1880 | 2,615,608 | 235,404 | 9,416,000 | 82,400 |
| 1875 | 1,686,516 | 84,325 | 3,373,000 | 29,500 |
| 1872 | 1,317,637 | 52,705 | 2,108,000 | 18,400 |
+------------+---------------------------+-------------+-----------+
_Exports_
+------------+------------------------+-------------------------+
| Year | Cotton-seed. | Oil. |
| ending +-----------+------------+------------+------------+
|June 30.[2] | Quantity. | Value. | Quantity. | Value. |
+------------+-----------+------------+------------+------------+
| | Tons. | $ | Gallons. | $ |
| 1909 | | | | |
| 1908 | 14,239 | 353,213 | 41,029,991 | 17,226,451 |
| 1907 | 8,814 | 209,493 | 41,880,304 | 17,074,403 |
| 1906 | 11,859 | 268,330 | 43,793,519 | 13,673,370 |
| 1904 | 6,430 | 141,174 | 29,013,743 | 10,717,280 |
| 1902 | 28,202 | 509,627 | 33,042,848 | 12,992,393 |
| 1900 | 24,928 | 346,230 | 46,902,390 | 14,127,538 |
| 1890 | 3,830 | 74,575 | 13,384,385 | 5,219,178 |
| 1880 | 6,071 | 134,116 | 6,997,796 | 3,225,414 |
| 1875 | 2,658 | 63,128 | 417,387 | 216,640 |
| 1872 | 3,180 | 72,212 | 547,165 | 293,546 |
+------------+-----------+------------+------------+------------+
| Year | Cake and Meal. |
| ending +-----------+------------+
| June 30. | Quantity. | Value. |
+------------+-----------+------------+
| | Tons. | $ |
| 1909 | | |
| 1908 | 464,644 | 11,889,415 |
| 1907 | 670,484 | 17,062,594 |
| 1906 | 555,417 | 13,073,100 |
| 1904 | 410,175 | 9,134,088 |
| 1902 | 525,233 | 12,271,009 |
| 1900 | 571,852 | 11,229,188 |
| 1890 | [3] | |
| 1880 | | |
| 1875 | | |
| 1872 | | |
+------------+-----------+------------+
[Footnote 2: The figures in this table relate to the seed crop of the
previous year.]
[Footnote 3: Not separately shown.]
INDEX
Acetic acid, 9.
=Acid=—
Acetic, 9.
Arachidic, 9.
Behenic, 9.
Butyric, 9.
Capric, 9.
Caproic, 9.
Caprylic, 9.
Carnaubic, 9.
Cerotic, 10.
Daturic, 9.
Doeglic, 10.
Eleomargaric, 12.
Eleostearic, 12.
Erucic, 10.
Ficocerylic, 9.
Hyænic, 10.
Hypogæic, 10.
Isolinolenic, 12.
Isovaleric, 9.
Jecoric, 12.
Lauric, 9.
Lignoceric, 9.
Linolenic, 12.
Linolic, 12.
Margaric, 67.
Melissic, 10.
Moringic, 10.
Myristic, 9.
Oleic, 10.
Palmitic, 9.
Physetoleic, 10.
Pisangcerylic, 10.
Psyllostearylic, 10.
Rapic, 10.
Ricinolenic, 12.
Stearic, 9.
Tariric, 12.
Telfairic, 12.
Theobromic, 10.
Tiglic, 10.
Acidity of lard, 61-62.
Acids, volatile fatty, 10.
Alkaline earths, refining with, 28.
Analysis of oil, 89.
Arachidic acid, 9.
Arachis oil, 18, 77, 78.
adulteration of, 78.
analysis of, 78.
constituents of, 78.
Artificial colouring matter in butter, 55, 122.
Artificial flavouring in margarine, 71, 72.
Azo dyes, 71.
Barium values, 55.
Bechi’s test, 107.
Behenic acid, 9.
Bleaching of oils, 29.
with charcoal, 29.
fuller’s earth, 30.
hydrosulphites, 33.
hyposulphites, 33.
organic peroxides, 33.
ozone, 32.
sodium bisulphite, 33.
Borax in butter, 46.
Boric acid in butter, 46.
Borneo tallow, 87.
Boron compounds, 124.
Bromine absorption, 96.
thermal value, 105.
Brown grease, 58.
=Butter=, 3, 39, 40.
abnormal, 49.
analysis of, 109.
artificial colouring matters in, 55, 122.
borax in, 46.
boric acid in, 46.
cacao, 19, 84, 85.
casein in, 121.
chemical characteristics of, 48-52.
cocoanut oil in, 53, 54, 112.
commercial, 40.
composition of, 40.
curd in, 41.
Dutch, 67.
fat, 39, 40.
composition of, 40.
Illipé, 87.
influence of food of cows on, 52.
Irish, 52.
keeping properties of, 42-44.
Mahua, 87.
milk-blended, 41.
nut, 72.
oil, 16, 45.
physical characteristics of, 47.
preservatives in, 46-47, 124.
“process,” 44-46.
rancidity of, 44.
refractometric examination of, 48.
renovated, 44-46.
salt in, 41.
shea, 21, 87.
solubility of, 47.
vegetable, 16, 72.
water in, 41.
Butterine, 67.
Butyric acid, 9.
Butyrin, 6, 7.
Butyro-refractometer, 48.
Cacao butter, 19, 84-85.
Cadmium values, 55.
Capric acid, 9.
Caprin, 6.
Caproic acid, 9.
Caproin, 6.
Caprylic acid, 9.
Caprylin, 6.
Carnaubic acid, 9.
Casein in butter, 121.
Caustic soda, refining with, 26.
Cerotic acid, 10.
Ceylon oil, 16.
Charcoal, bleaching with, 29.
Cheese, 130.
Chemical methods of refining, 132.
Chocolate, 84, 132.
Chocolate cream, 85.
Chocolate fats, 84-88, 133.
Choice lard, 58.
Choice steam lard, 58.
Cochin oil, 16.
Cocoa, 84.
Cocoanut oil, 15.
analyses of, 86.
deodorisation of, 34.
in butter, 53, 54, 112.
stearins, 85, 86.
Colouring matter for margarine, 71.
matters, artificial, in butter, 55.
Combustion of fats, 2.
Commercial butter, 40.
grades of lard, 58-59.
Constitution of fats, 1, 3.
oils, 1, 3.
Corn oil, 83, 84.
Cotton-seed oil, 16, 80, 107.
winter, 81.
stearin, 17, 81.
Coumarine, 72.
Crystals of lard, 59, 60.
Culinary oils, 74.
Curd, amount of, in butter, 41.
Daturic acid, 9.
Decroline, 33.
Demargarinated oil, 76.
Deodorisation of cocoanut oil, 34-36.
of fats, 34.
Digestibility of fats, oils, 3.
Diglycerides, 5.
Dika fat, 87.
Doeglic acid, 10.
Dripping, 2, 14, 65.
Dutch butter, 67.
Dyes, azo, 71.
Earth-nut oil, 18, 77, 108.
Elaidin test, 64, 79.
Eleomargaric acid, 12.
Eleostearic acid, 12.
Erucic acid, 10.
Fat as food, 1.
Fat, butter, 39-40.
Dika, 87.
goose, 6.
Illipé, 87.
Mkani, 87.
Tankawang, 87.
turkey, 6.
Fats, chocolate, 84-88.
constitution of, 1, 3.
deodorisation of, 34.
other vegetable, 86.
treatment of rancid, 36-38.
Fatty acids, volatile, 8, 10.
Fendler’s patent, 71.
Ficocerylic acid, 9.
Filtration, methods of, 25.
Flare lard, 60.
Flavouring, artificial, in margarine, 71-72.
Fluorides, 128.
Food, fat as, 1.
value, 3.
Foots, 27, 80.
Formulæ for margarine, 69-70.
(U.S.A.) Cheap Grade, 70.
High Grade, 70.
Medium High Grade, 70.
Free fatty acids, 91.
French salad oil, 79.
oil trade, 142.
Fuller’s earth, bleaching with, 30.
Gaboon fat, 87.
Gingelly oil, 79.
Glycerides, 3, 4.
Goose fat, 6.
Grades, commercial, of lard, 58-59.
Grease, brown, 58.
pig’s foot, 58.
white, 58.
yellow, 58.
Guts, 58.
Halphen’s test, 107.
Hehner value, 49, 118.
Huiles d’enfer, 75.
tournantes, 75.
Hyænic acid, 10.
Hydraldite C., 33.
Hydrosulphites, bleaching with, 33.
Hypogæic acid, 10.
Hyposulphites, bleaching with, 33.
Illipé butter, 87.
fat, 87.
Iodine value, 94.
of lard, 63, 64.
Irish butter, 52.
Isolinolenic acid, 12.
Isovaleric acid, 9.
Isovalerin, 6.
Jecoric acid, 12.
Keeping properties of butter, 42-44.
=Lard=, 15, 56.
acidity of, 61-62.
amount of water in, 62-63.
analysis of, 61.
choice (steam), 58.
commercial grades, 58-59.
composition of, 59.
crystals, 59-60.
examination of, 130.
flare, 60.
guts, 58.
influence of food on, 60-61.
iodine value, 63-64.
leaf, 58, 60.
neutral, 58.
oil, 15, 64.
prime, 58.
pure, 58.
rendering of, 56-58.
water in, 62.
Lauric acid, 9.
Laurin, 6, 7.
Lignoceric acid, 9.
Linde’s process, 24.
Linolenic acid, 9, 12.
Linolic acid, 9, 12.
Mafura tallow, 87.
Mahua butter, 87.
Maize oil, 16, 83-84.
analyses of, 84.
Malabar tallow, 87.
Margaric acid, 67.
=Margarine=, 3, 14, 65-66.
analyses of, 129.
artificial flavouring, 71-72.
colouring matter, 71.
composition of, 70.
English formula, 70.
formulæ for, 69-70.
Cheap Grade, 70.
High Grade, 70.
Medium High Grade, 70.
manufacture of, 66.
modern process, 68-69.
Margosa oil, 21.
Maumené test, 103.
Mège-Mouries process, 65-68.
Melissic acid, 10.
Methods of filtration, 25.
Milk-blended butter, 41.
Mixed glyceride, 5.
Mkani fat, 87.
Modern process margarine, 68-69.
Monoglycerides, 5.
Moringic acid, 10.
Mowrah-seed oil, 21.
Myristic acid, 9.
Myristin, 6, 7.
Nagel’s process, 37.
Neutral lard, 56, 68-69.
Nut butter, 72.
salad oils, 77.
=Oil=—
Arachis, 18, 77-78.
Butter, 16, 45.
Ceylon, 16.
Cochin, 16.
Cocoanut, 15.
Corn, 83, 84.
Cotton seed, 16, 80-82.
Demargarinated, 76.
Earth-nut, 18.
French salad, 79.
Gingelly, 79.
Lard, 15, 64.
Maize, 16, 83-84.
Margosa, 21.
Mowrah-seed, 21.
Nut salad, 77.
Olive, 17, 74-77.
Palm, 20, 72.
kernel, 18.
nut, 18.
Peanut, 18.
Poppy, 83.
Sesame, 18, 79-80.
Soya bean, 20.
Sunflower (seed), 19, 82-83.
Teel, 79.
of Theobroma, 19.
Virgin, 74, 76.
Winter cotton-seed, 81.
=Oils=—
bleaching of, 29.
constitution of, 1, 3.
pyrene, 75.
salad, 74-88.
semi-drying, 79, 81.
sulphocarbon, 75.
summer, 25, 80.
winter, 25, 76.
Oleic acid, 9, 10.
Olein, 6, 8.
Oleomargarine, 66, 67, 68, 70.
Oleo oil, 67, 69, 70.
Oleo-refractometer, 64.
Oleo-stearin, 69.
Olive oil, 17, 74-77, 106.
Organic peroxides, bleaching with, 33.
Ozonair apparatus, 32.
Ozone, bleaching with, 32.
Palm oil, 20, 72.
kernel oil, 18.
analyses of, 86.
stearin, 85, 86.
Palm-nut oil, 18.
stearin, 85.
Palmitic acid, 9.
Palmitin, 6, 7.
Peanut oil, 18, 77, 108.
Peroxides, bleaching with organic, 33.
Per-salts, 33.
Physetoleic acid, 10.
Physical characteristics of butter, 47.
methods of refining, 23.
Physiological considerations, 2.
Phytosteryl (acetate) test, 64, 82, 101.
Pig’s foot grease, 58.
Piney tallow, 87.
Pisangcerylic acid, 10.
Polenské’s test, 113.
Poppy oil, 83.
Premier jus, 14, 30, 68.
Preservatives in butter, 46, 47.
Prime steam lard, 58.
“Process” butter, 44-46.
Linde’s, 24.
Mège-Mouries, 65-68.
Nagel’s, 37.
Psyllostearylic acid, 10.
Pyrene oils, 75.
Rancid fats, treatment of, 36, 37, 38.
Rancidity in oils, 36.
of butter, 44.
Rapic acid, 10.
Raw materials, 14.
Refining with alkaline earths, 28.
caustic soda, 26.
sodium carbonate, 28.
silicate, 28.
of oils, 23.
Refractive index, 98.
Refractometer, butyro, 48.
Refractometric examination of butter, 48.
Reichert value, 49-50.
Reichert-Meissl value, 50-52.
process, 111.
Removal of stearin, 25.
Rendering of lard, 56-58.
Renovated butter, 44-46.
Ricinoleic acid, 9, 12.
Ricinolein, 6.
Rongalite C., 33.
Salad oils, 74-88.
Salt, amount of, in butter, 41.
oils, 121.
Saponification value, 92.
Semi-drying oils, 79, 81.
Sesame oil, 18, 79, 80.
Sesamin, 79.
Sesamol, 79.
Shea butter, 21, 87.
Sodium bisulphite, bleaching with, 33.
carbonate, refining with, 28.
silicate, refining with, 28.
Solidification point, 96.
Solubility of butter, 47.
Sorting tests, 48.
Soya bean oil, 20.
Spanish oil trade, 140.
Specific gravity, 90.
Statistics of oil trade, 137.
Steam lard, choice, 58.
Stearic acid, 9.
Stearin, 6, 8, 25, 76, 77, 79, 86.
cotton-seed, 17.
removal of, 25.
Stearins, cocoanut oil, 85, 86.
palm-kernel oil, 85, 86.
Suet, 14.
Sulphocarbon oils, 75.
Summer oils, 25, 80.
Sunflower(-seed) oil, 19, 82-83.
Tallow, 14.
Borneo, 87.
Mafura, 87.
Malabar, 87.
Piney, 87.
unrendered, 15.
Tankawang fat, 87.
Tariric acid, 12.
Teel oil, 79.
Telfairic acid, 12.
Test, elaidin, 64, 79.
phytosteryl, 64.
Valenta’s, 48.
Tests, sorting, 48.
Theobroma oil, 19.
Theobromic acid, 10.
Tiglic acid, 10.
Treatment of rancid fats, 36, 37, 38.
Triglycerides, 5, 6.
Turkey fat, 6.
Unrendered tallow, 15.
Unsaponifiable matter, 99.
Valenta’s test, 48, 102.
Value, food, 3.
Hehner, 49.
iodine, of lard, 63, 64.
Reichert, 49, 50.
Reichert-Meissl, 50-52.
Values, barium, 55.
Values, cadmium, 55.
Vegetable butter, 16, 72.
fats, other, 86.
Virgin oil, 74, 76.
Volatile fatty acids, 10.
Water, amount of, in butter, 41.
lard, 62, 63.
Watts’ bichromate process of bleaching, 31.
White grease, 58.
Winter cotton-seed oil, 81.
Winter oils, 25, 76.
Yellow grease, 58.
_Printed by_ MORRISON & GIBB LIMITED, _Edinburgh_