Animal fat

“ The fat of an animal appears to be the provision of nature for the maintenance of life during a certain period under circumstances of privation. Hence it is that a lean animal suffers more from cold than a fat one, and is also sooner starved.
“The origin of fat in the animal body has recently been made the subject of much animated discussion; on the one hand, it was contended that satisfactory evidence exists of the conversion of starch and saccharine substances into fat, by separation of carbon and oxygen, the change somewhat resembling that of the vinous fermentation ”

“ With sheep—as well as with all other animals—much or prolonged exercise in pursuit of food, or otherwise, is unfavorable to taking on fat. Some seem to forget, in their earnest advocacy of the merits of the different breeds, that the general physical laws which control the development of all the animal tissues as well as functions, are uniform. Better organs will, doubtless, make a better appropriation of animal food; and they may be taught, so to speak, to appropriate it in particular directions: in one breed, more especially to the production of fat ”

“ Should an animal whose body contains three times as much fat as lean flesh, be supplied with food containing three times as much fat-formers as flesh-formers? To these questions there is some difficulty in replying. There is a relationship between the composition of the body of an animal and that of its food; but the relationship varies so greatly that it is impossible to determine with any degree of accuracy the quantity of fat-formers which is required to produce a given weight of fat in animals, taken in globo. ”

“ The flesh of an over-fattened animal differs from that of a lean, or moderately fat one, in containing an exceedingly high proportion of fat; but it has not been proved that the fat of prize animals differs from the fat of lean kine, or that it is less wholesome or nutritious. Be the flesh of those exceedingly fat animals unwholesome or not, there are thousands, ay, millions of persons, to whom its greasy quality renders it peculiarly acceptable; and as for those who dislike fat—they do not usually invest their money in the flesh of prize sheep or oxen. ”

“ Grape sugar, woody fibre, and vegetable and animal fats and oils are made up of the same elements, but in different proportions, the last containing much more carbon and hydrogen than those above specified. In the fattening animals, it is supposed the vegetable fats and oils are immediately transferred to the fat cells, undergoing only such slight modification as perfectly adapts them to the animal economy, while respiration is supplied by the other enumerated vegetable matters. ”

“ When, however, we remark, that fat is taken up in some diseases where the appetite is impaired; and that torpid animals, before hibernation, have a large quantity of it accumulated, and come out of that state quite emaciated: 372 and that bees, who have no fat in their bodies, lay up a stock of food, having the same chemical properties, against their hibernating season; it appears very probable, that one use of fat is to form a reservoir of nutriment, which supplies the wants of an animal when food is not introduced by the stomach. ”

“ Fattening is a secretive power which grazing animals possess, enabling them to lay by a store of the superfluous [184] food which they take for seasons of cold or scarcity. It collects round the angular bones of the animal, and gives the appearance of rotundity; hence the tendency to deposit fat is indicated, as has been stated, by a roundness of form, as opposed to the fatness of a milk-secreting animal. ”

“ SAVE FAT Reasons Why Our Government Asks Us to Save Fat, With Practical Recipes for Fat Conservation
With the world-wide decrease of animal production, animal fats are now growing so scarce that the world is being scoured for new sources of supply. Our Government has asked the housewife to conserve all the fats that come to her home and utilize them to the best advantage. ”

“ If the animal be deprived of nutriment, it immediately begins to lose weight, because its functions must continue—carbon must still be converted into carbonic acid to maintain respiration—and the excretions be eliminated, although diminished in quantity, because they no longer contain the undigested portion of the daily food, and the substances already stored up in [Pg 278] the body are consumed to maintain the functions of life. Universal experience has shewn that, under such circumstances, the fat which has accumulated in various parts of the body disappears, and the animal becomes lean ”

“ Naturally inclined to corpulence and gluttony, they easily acquire an enormous bulk; and when fat has once begun to accumulate, the animal eats little, breathes with difficulty, becomes inert, unable to sustain his own weight, and deficient in sensation. We have seen wretched pigs so fat that they were obliged to be lifted or dragged out of the sty whenever it was necessary to move them. ”

“ That per cent of animal fats contained in the ordinary meat diet is quite as wholesome as any other element of nutrition secured from animal sources. However, with the splendid supply of vegetable fats civilized people have to draw upon, the use of animal fats cannot be recommended in any form except that of cream and butter, and when we consider the expense of these by comparison with many pure vegetable fats, our sense of ordinary economy would bid us discard them. ”

“ The quantity of fat, however, which is produced in the animal mechanism, from purely nitrogenous food appears to be relatively very small. No animal is capable of subsisting solely on muscle-forming materials, no matter how abundantly supplied. The food of the Carnivora contains a large proportion of fat, and the nutriment of the Herbivora is largely made up of starch and other fat-formers. ”

“ This care pursued for two or three months is sufficient to make them fleshy and fat; but this fat, which originates from the great quantities of water drank by the animal, is only a kind of pursy swelling, and would soon occasion the rot; it is therefore necessary to kill them immediately when they acquire this false fat: even their flesh, instead of having become firm and juicy, is frequently the more flat and insipid. If we would have good mutton, besides feeding them in the dew and giving them plenty of water, it is necessary they should have more succulent food than grass. ”

“ The fats eaten are not stored in the body directly, but the body constructs its fats from those eaten, and from other substances in food,—according to some authorities from the carbohydrates and proteids, and according to others from proteids alone.
Fats are stored away as fat, furnish heat, and are used for energy; at least, it is probable that at times they are put to the latter use. The fats laid by in the body for future use last in cases of starvation quite a long time, depending, of course, upon the amount. At such times a fat animal will live longer than a lean one. ”

“ The whey of milk is rich in them; but they do not exist in pure butter, in starch, or in sugar.
Fat is a much more abundant constituent of the animal body than is generally supposed, That this substance should [15] constitute the greater portion of the weight of an obese pig seems probable enough; but few are aware that even in a lean sheep there is 50 per cent. more fat than lean.
For a very accurate knowledge of the relative proportions of the fatty, nitrogenous, and mineral constituents of the carcasses of animals used as human food, we are indebted to Messrs. Lawes and Gilbert. ”

“ On the other hand, it is claimed that if an animal is first starved, so that fat disappears from the body, and then poisoned with phosphorous, no fat appears in the liver. There is too other evidence of an experimental nature to show that the fat of fatty degeneration is fat transported from the usual depots of fat and simply deposited in the degenerating cells. ”

“ The amount of fat in meats, however, is more important; and depends largely upon how well the animal has been fed. There is usually the least amount of fat in mutton, more in {29}beef, and by far the greatest amount in pork. This fat adds to the fuel value of meat, but makes it a little slower of digestion; and its presence in large amounts in pork, together with the fact that it lies, not only in layers and streaks, but also mixed in between the fibres of the lean as well has caused this meat to be regarded as richer and more difficult of digestion than either beef or mutton. ”

“ Characteristics of Fats.—The fats are all insoluble in water, and only partially so in cold alcohol, but they dissolve readily in ether. As a rule, the fat occurring in the animal body is more or less characteristic of the species. For example, animals that live on land have a harder fat than those living in the water ”

“ I have often wished to convey in language that idea or sensation we acquire by the touch or feel of our fingers, which enables us to form a judgment when we are handling an animal intended to be fatted, but I have as often found myself unequal to that wish. It is very easy to know where an animal is fattest which is already made fat, because we can evidently feel a substance or quantity of fat—all those parts which are denominated the fatting points ”

“ Of the three classes of food constituents, two—the mineral and nitrogenous—are recoverable in the animal's body and manure; the non-nitrogenous is partly recoverable in the fat. I shall take the case of a sheep, which will consume weekly per 100 lbs. of its weight, 12 lbs. of fat-formers, and 3 lbs. of flesh-formers. Twelve per cent. of the fat-formers will be retained in the increase, but the rest will be expended in keeping the animal warm, and the products of its combustion—carbonic acid and water—will be useless to the farmer. ”

“ Hence, a well-fatted animal always commands a better price per pound than one imperfectly fed, and the parts selected as the primest beef are precisely the parts which contain the largest deposits of fat. The rump, the crop, and the sirloin, the very favorite cuts,—which always command from twenty to twenty-five per cent. more than any other part of the ox,—are just those parts on which the largest quantities of fat are found ”

“ The larger the quantity of food which a fattening animal can be made to consume daily, with a good appetite, or which it can digest thoroughly, the greater will be the amount of flesh and fat gained, in proportion to the whole quantity of food consumed.
Substances in which the nutriment is much concentrated should be fed with care. There is danger, especially when the bird is first put to feed, that more may be eaten at once than the digestive organs can manage. Meal of Indian corn is highly nutritive; and, when properly fed, causes fowls to fatten faster than almost any other food. ”

“ Besides so many benefits and useful services conferred on man by this valuable animal, his fat, in a commercial sense, is quite as important as his flesh, and brings a price equal to the best joints in the carcase. This fat is rendered, or melted out of the caul, or membrane in which it is contained, by boiling water, and, while liquid, run into prepared bladders, when, under the name of lard, it becomes an article of extensive trade and value. ”

“ The fats belong to a group of substances that are strongly surface-active, while the products of disintegration produced by their decomposition, such as alcohol and fatty acids, possess no marked influence over surface-tension. If plasma of a normal animal be mixed with any kind of fat, such as tributyrin, and the mixture be allowed to flow from a capillary tube, a certain number of drops escape in a given time. But if any fat gets into the animal's circulation by whatever means, then the number of drops escaping through the capillary tube decreases. ”

“ In such circumstances the mucilaginous or saccharine secretions especially, perhaps the most general of all, may be absorbed into the vegetable constitution; just as fat is into the animal one, during the existence of any disease that interrupts the ordinary supplies of food, or interferes with its due appropriation. It is well known that such animals as sleep through the winter, grow fat in the autumn and awake very lean in the spring. ”

“ The proper ratio for feeding fowls has received much discussion. Dietetic authorities mostly agree that about 1:5 is the best for maintenance of animal life generally, and more specifically that there should be of albuminoids about 18 parts in 100, of fats 7 and carbohydrates 75. That should suffice for growing chickens; but it is fairly obvious that fowls fattening may require more fat, while the constant production of eggs, whose high ratio is shown in the analyses, must require a larger amount of albuminoids. ”

“ It has been shown for instance by Dr Hopkins in Cambridge, and his results have been confirmed at the Carnegie Institute in America, that young rats fail to thrive on a diet composed of suitable amounts of purified protein, fat, starch, and ash, but that they 134 thrive and grow normally on such a diet if there is added a trace of milk or other fresh animal or vegetable substance far too small to influence either the protein content or the energy-value. ”

“ Dogs, geese, and other animals fed exclusively upon albumen or white of egg rapidly decreased in weight, and after presenting all the symptoms of starvation, died in three or four weeks.8 The fat of the bodies of the Carnivora is almost entirely formed—and probably with little if any alteration—from the fatty constituents of their food. Herbivorous animals, on the contrary, derive nearly all their fat from starch, sugar, gum, cellulose, and other non-nitrogenous, but not fatty, materials. ”