a

It should be remembered that chicory, especially the older roots, contains a small proportion of woody fibre, so that care must be exercised not to confound this fibre with extraneous woody fibre or sawdust introduced for the purpose of adulteration. If the quantity of fibre present be very small, and it agree with that of chicory in its structure as seen under the microscope, there can be little doubt but that the fibre belongs to the root of chicory.

On the detection of caramel or burnt sugar.--When the water added to any sample of ground coffee becomes deeply and quickly coloured, and when on examination with the microscope it is ascertained that no foreign vegetable is present, there will be good reason for supposing that it contains burnt sugar.

Again, when shining black particles are perceptible in the coffee, and these slowly dissolve in water, giving rise to a dark-coloured solution, it undoubtedly contains the substance in question. Sometimes, when the particles are too small to be discerned by the naked eye, they may be seen under the microscope, and their solution in water watched.

Again, the presence of burnt sugаr may be detected by adopting the following process :-From a weighed quantity of dried coffee an infusion in cold water is to be prepared ; this must be evaporated in a water-bath, dried, and tasted. If the extract be dark-coloured, brittle, and possess the bitter taste of burnt sugar, no doubt remains as to the presence of that substance.

We are unacquainted with any process by which the quantity of burnt sugar present can be accurately determined, seeing that the extract furnished by pure coffee varies very greatly, and that of adulterated coffee to a still more considerable extent; while also the composition of the burnt sugar is so much changed, that its exact amount cannot be determined in the same manner as grape sugar, but this method gives, at least approximately, the quantity of burnt sugar present.

On the detection of Venetian red.—Sometimes when the Venetian red has been carelessly incorporated with the coffee, particles of it may be detected with the naked eye; but it is not often that it can be discovered in this way. The process to be adopted in ordinary cases is as follows:-A portion of the suspected coffee is to be incinerated, and the colour of the ash noted; if this be deeply coloured and of a rusty red or yellowish hue, then Venetian red, reddle, or some analogous earthy substance has been mixed with the coffee.

If be desired to ascertain the exact amount of iron present, a weighed quantity of the article should be incinerated, the ash boiled with strong hydrochloric acid, and in the solution the iron estimated by one or the other of the methods given under • Tea.'

On the estimation of silica.—Silica may occur in one or both of two forms-namely, as chemically bound silica, entering into the composition of the vegetable substance or substances forming the article, and,

a

secondly, as extraneous silica or sand. They may be thus discriminated and estimated separately; a weighed quantity of the article, say three grammes, are incinerated in a platinum capsule, the ash is boiled with concentrated hydrochloric acid, and evaporated to dryness on the water-bath. The dried residue is moistened with hydrochloric acid and treated with boiling water; the silica only in its two forms will remain undissolved. It is separated by filtration, incinerated, and weighed. Thus the total amount of silica is ascertained. It is then boiled for some time with a strong solution of carbonate of soda, which only dissolves the chemically bound silica, or that part which had entered into the composition of the ash. The sand remains undissolved, is collected on a filter, washed with boiling water, incinerated, and weighed. The loss of weight gives the proportion of chemically combined silica.

1

CHAPTER VI.

CHICORY AND ITS ADULTERATIONS.

DEFINITION OF ADULTERATION.

Any added foreign vegetable or mineral substance. CHORY, succory, or wild endive, Cychorium Intybus, belongs to the same natural family of plants as the dandelion, namely, Compusite. It is indigenous, and may be seen growing in various parts of the country, by the road or hedge-side; it may be recognised by the compound character of its flowers, and their bright and beautiful blue colour. It blossoms in the months of August and September. In its natural state the stem rises from one to three feet high, but when cultivated it shoots to the height of five or six feet. The root runs deep into the ground, and is white and fleshy, and yields a milky juice. It is cultivated to some extent in this country as an herbage plant, its excellence in this respect having been strongly insisted upon by the late Arthur Young.

In Germany, and in some parts of the Netherlands and in France, it is extensively cultivated for the sake of its root, which is used as a substitute for coffee. The root is taken up just before the plant blossoms, and when roasted, lard or sometimes butter is added in the proportion of 2 lbs. of lard to 1 cwt. of the kiln-dried root. When ground and exposed to the air, chicory absorbs water readily, and becomes moist and clammy. When prepared on a large scale, the roots are partially dried and sold to the manufacturers of the article, who wash them, cut them in pieces, kiln-dry them, and grind them between fluted rollers into a powder.

The powder of the roasted roots bears striking resemblance to ground coffee, and is still extensively used in Prussia, and other parts of Germany; but as it wants the essential oil, and the rich aromatic flavour of coffee, the caffeine and the caffeo-tannic acid, it has little in common with the latter, except its colour, and has nothing to recommend it beyond its cheapness.

Notwithstanding that chicory' has nothing to recommend it except its cheapness,' and that it is used exclusively to adulterate coffee, it has of late years been raised in great quantity in this country, in the counties of Surrey, Bedford, and York.

Foreign chicory is considered to be greatly superior to that of English growth, and is consequently much dearer.

COMPOSITION OF CHICORY.

Chicory root has been subjected to examination and analysis by Dr. Letheby at the author's request, and the following is his report on the results obtained, namely,

1st. In its recent, or raw state.

( 2nd. In the kiln-dried condition.

3rd. In the roasted and powdered form, as it is used for the adulteration of coffee.

The raw root furnishes a milky juice, which owes its opacity to the presence of an inert vegetable substance named Inuline. The juice is very bitter, and, when filtered and heated, it shows, by its turbidity, that it contains a small quantity of albumen.

'When macerated in cold water, it yields about 13 per cent. of solid matter or extractive, which gives to the solution a very bitter taste. By Fehling's test, it was found that the raw root contained 1.1 per cent. of grape-sugar or glucose.

The kiln-dried root possesses all the characters of the preceding, but in a higher degree, for water extracts about 50 per cent. of solid matter; and the solution furnished to Fehling's test as much as 10.5 per cent. of sugar.

'Neither of these specimens exhibited the least trace of starch, but by boiling in water, filtering, and cooling, they yielded a small quantity of a white powder, which has all the characters of Inuline.

The absence of starch in the state in which the root is ordinarily used is also conclusively shown by means of the microscope; and we find that the tissue contains abundance of cellulose, which, by the action of strong sulphuric acid, gives a product that renders iodine blue.

"The roasted chicory root yields from 45 to 65 per cent. of soluble extractive. Its solution in water is acid, and it does not possess the peculiar bitter taste of the raw root; but the taste of the liquid is more like that of burnt sugar. The copper test shows the presence of from 10 to 13 per cent. of sugar.

'The following analyses represent the percentage composition of the root in its different conditions:·

Messrs. Graham, Stenhouse, and Campbell 1 found in four samples of chicory the following percentages of grape-sugar:—

Raw. Roasted.