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employed in the Preparation and Storage of Food; while nearly the whole of the articles which are not entirely new have been much extended or entirely re-written. The Author has therefore deemed it best to bring the book out under a new title, and not as a fresh edition of his former work, ‘Adulterations Detected.'

He now desires to record the obligations he is under to his assistant, Mr. Otto Hehner, who has ably and cheerfully rendered him much valuable aid, more particularly in the purely chemical portions of the work.

Sr. CATHERINE'S HOUSE, VENTNOR :

November 1875.

CONTENTS.

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XV. SAGO AND ITS ADULTERATIONS

XVI. TAPIOCA AND ITS ADULTERATIONS

XVII. PROPRIETARY ALIMENTARY PREPARATIONS

XVIII. MILK AND ITS ADULTERATIONS

XIX. BUTTER AND ITS ADULTERATIONS

XX. CHEESE AND ITS ADULTERATIONS

XXI. LARD AND ITS ADULTERATIONS

XXII. ISINGLASS AND ITS ADULTERATIONS

XXIII. GELATIN AND ITS ADULTERATIONS

XXIV. UNWHOLESOME AND DISEASED MEAT .

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UNIVERSITY

CALIFORMA

FOOD:

ITS ADULTERATIONS

AND

THE METHODS OF THEIR DETECTION.

CHAPTER I.

ON FOOD, ITS FUNCTIONS AND QUANTITY. It will facilitate the comprehension of much that is to follow, and enable us to answer questions which will be often put to us as to the quality, genuineness, wholesomeness, and quantity of the various kinds of food consumed, if we first bestow a few observations upon the functions performed by the several classes and kinds of food, and the amounts necessary to the growth, sustenance, and maintenance of the body in a state of health.

The bodies of men and animals are built up of several substances; some of these, from the fact of their containing nitrogen, are called nitrogenous; others, being destitute of that principle, are termed nonnitrogenous, or carbonaceous, mineral constituents, and water.

The principal nitrogenous substances of the animal body are fibrin, found in the blood and muscles ; albumen and globulin, abounding in the blood; gelatine, in the bones, tendons, and ligaments; and casein, in milk; while the chief non-nitrogenous constituent is fat; they are identical in their ultimate composition, and contain carbon, hydrogen, nitrogen, oxygen, and sulphur, in the following proportions:Carbon

53-5 Hydrogen

7.0 Nitrogen.

15.8 Oxygen

22:1 Sulphur

1.6

100.0

a

Now, the vegetable has a composition resembling, in the main, that of the animal, it containing analogous nitrogenous substances, though usually in smaller amounts; while the fat is represented chiefly by

B

sugar and starch, though in some exceptional cases fat or oil is met with, as in the seeds of various plants. All the nitrogenous substances entering into the composition of the human and other animal bodies are derived, either directly or indirectly, from the vegetable kingdom, the vegetable being constructive and the animal destructive.

The nitrogenous elements are capable, under some circumstances, of furnishing both fat and sugar ; thus, there is evidence to show that the fatty matter of milk and the sugar of diabetes are thence derived, at least to some extent. Again, starch and sugar are sometimes transformed into fat, but the greater part of the fat of the body is derived from that contained in the food.

Notwithstanding this partial and occasional formation of fat from the nitrogenous, starchy, and saccharine elements of the food, each separate class is needed to sustain the body in a state of health. Thus, perfect health cannot be maintained for any length of time on nitrogenous food alone, even with water and the mineral constituents; and although it may be supported for a longer period on such food combined with fat, yet, for perfect health, the albuminates, fat, and the carbo-hydrates, as sugar and starch, are all necessary, though how the latter act in nutrition is not yet fully understood, since they do not enter into the composition of the tissues like the others. Further, it should be clearly understood that excess of lean meat increases the oxidation of the fat, thus tending to the reduction of obesity; excess of the carbo-hydrates acts in the same way.

Now, these several nitrogenous and non-nitrogenous constituents of the food are constantly undergoing change and destruction in ministering to the several necessities of the living animal organization, as the growth, sustenance, and waste of the body, its heat, electricity, and muscular force; and hence the necessity for a frequent supply of food. The various constituents of the food, having served the several purposes in the animal economy which have been already noticed, are eliminated from the system, the nitrogenous chiefly as urea, uric and hippuric acids, creatine and creatinine, and the non-nitrogenous in the forms of carbonic acid and water,

While starch and sugar only want as much oxygen for complete combustion as is required to combine with their carbon, fat needs a larger proportion, for it contains an excess of hydrogen, which consumes a proportionate amount of oxygen to form water. By the combustion of fat, therefore, more heat—2:4 times as much—is developed, than by an equal quantity of starch or sugar.

Now, the process of respiration is merely an act of combustion; the air carried to the lungs by inspiration is there deprived of much of its oxygen, while, in place of this gas, the expired air contains a proportionate quantity of carbonic acid, which is derived from the food introduced into the blood, and especially from its non-nitrogenous constituents, which may be termed heat producers,' for by their oxidation the heat of the body is chiefly obtained.

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