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nor albumen will continue to be eaten cent investigations have shown that by animals ; they soon cease to eat muscle - fibrine is really a different it, and during the period in which it substance, allied to, but not identical is taken they show unmistakable with blood-fibrine. signs of starvation.
Albumen and fibrine are found Albumen, then, is highly nutri- abundantly in vegetables the fortious; and if we estimated the nu- mer being most abundant in wheat, tritive value of various articles ac- rye, barley, oats, maize, and rice. It cording to their amounts of albumen, is found also in the oily seeds, such we should place caviare, ox-liver, and as almonds, nuts, &c. ; in the juices sweetbread at the top of the list
, of carrots, turnips, cauliflowers, aspaleaving the muscle of beef very far ragus, &c.* Fibrine is also abundant below them. The following table in the cereals, grape-juice, and juice shows the proportions of albumen of other vegetables. Although closely in 100 parts of various articles of allied to animal albumen and fibrine, food :
they are not identical with these subCaviare,
stances, differing from them both in Ox.liver,
composition and properties; but the Sweetbread,
differences are so slight, that vegeMuscle of pigeon,
table albumen easily passes into aniof veal,
3.02 mal albumen in the digestive proof chicken,
3.00 of beef,
2.02 Caseine is another of the albumiThis table is very instructive, as
nous substances, and may be reshowing the vanity of attempting by into which it readily passes. It forms
garded as a modification of albumen, a chemical analysis to assign the nutritive value of any food. The most
the curd, or coagulable matter of milk.
Unlike albumen, it does not coagunutritive of all these articles is noto
late by heat. If heated in an open riously beef, which, according to this analysis, should be least so.
vessel, an insoluble pellicle is formed
on the surface, as we often see in the discrepancy is lessened, but not removed, when we take into account
milk jug brought up with our coffee ;
but this effect is produced by the the quantity of fibrine contained in these articles, namely
action of the oxygen of the atmo
sphere. The proportion of caseine Sweetbread,
8 in different kinds of milk is as folVeal (muscle),
19 Chicken (muscle),
4.48 Beef (muscle),
4.50 Fibrine is liquid in the serum of
4.02 Asses' milk,
1.82 the blood, and is very closely allied
1.52 to albumen-indeed, for a long while was supposed to be identical with it It thus appears, we hope without and with the fibrine of muscle, which derogation to human dignity, that is now more accurately called muscu- asses' milk is considerably more like line (by Lehmann syntonin). When that on which we were suckled, than the blood is drawn from the body, any of the others. fibrine passes from the liquid to the Caseine forms the chief ingredient solid state, and coagulates into what of cheese. It is an important eleis called the clot, which is nothing ment, as we see by its presence in but solid fibrine enclosing some of milk. “ The young animal receives, the red corpuscles. It was formerly in the form of caseine, the chief consupposed that this solidification was stituent of the mother's blood. To all that took place when blood fibrine convert caseine into blood, no foreign passed into muscular fibre; but re- substance is required; and in the con
* Albumen forms three compounds — basic, acid, and neutral. In the white of egg, and in the serum of blood, it is a basic albuminate of soda. In certain diseases it is a neutral albuminate in the blood.
version of the mother's blood into herbivora have more fibrine than carcaseine, no elements of the consti- nivora, birds have more than both. tuents of blood have been separated. Gluten is not found in animals, but When chemically examined, caseine exists abundantly in vegetables, and is found to contain a much larger is the most important of all the nitroproportion of the earth of bones than genous substances, because, as we blood does, and that in a very soluble have seen, it is capable of supporting form, capable of reaching every part life when given alone. “ It is the of the body. Thus, even in the ear- presence of gluten in wheaten flour liest period of its life, the develop- that renders it pre-eminently nutriment of the organs in which vitality tious; and its viscidity or tenacity resides is, in the carnivorous animal, confers upon that species of flour its dependent on the supply of a sub- peculiar excellence for the manufacstance identical in organic composi- ture of maccaroni, vermicelli, and tion with the chief constituents of similar pastes, which are made by a its blood.” *
Caseine is found in kind of wiredrawing, and for which beans, pease, lentils, almonds, nuts, the wheat of the south of Europe is and perhaps in all vegetable juices. peculiarly adapted." + The following
These three bodies albumen, table, which is borrowed from Dr fibrine, and caseine- -are not inaptly Pereira's work, gives the proportions designated “protein - bodies," even of gluten in 100 parts of various now that Mulder's idea of an organic vegetables :radical, named by him “protein,” has Wheat, Middlesex (average crop), 19.0 been generally given up. In the egg
24. 0 we see caseine arise from albumen, Thick-skinned Sicilian, 23. 0 and in digestion caseine passes back
20. O again into albumen. Fibrine, again, North American,
22. 5 appears to be only albumen with Barley, Norfolk,
0 more oxygen ; and it may be easily Oats, Scotland,
8. 7 reconverted into albumen by nitrate Rye, Yorkshire,
10. 9 of potash. It differs from albumen Rice, Carolina,
3.60 in assuming something of definite
5.75 structure when coagulated — fibril
Maize, lating, which albumen never does.
3, 5 There are many unexplained facts
4. 0 known respecting fibrine, which,when
0.1 explained, may clear away other ob- Cabbage,
0.8 scurities. Lehmann found, by experiments on himself, that animal diet These four albuminoid substances, produced more fibrine in his blood namely albumen, fibrine, caseine, and than was produced by vegetable diet gluten, are remarkable among other --a fact seemingly at variance with things for their extreme instability, the fact that, during starvation, the —the readiness with which they are quantity of fibrine is increased, as it transformed, or decomposed. It is is also during acute inflammations. this alterability which renders them Thus, animal diet, known to be nu- peculiarly apt to act as ferments, and tritious, produces a result known to to induce chemical changes in the be characteristic of inflammation and substances with which they come in starvation. Nor does the difficulty contact. It is on this alterability cease here: the blood of the vege- that their great value in nutrition table feeders, among animals, has depends. Further, we must remark more fibrine than that of the flesh- that, no matter what is the form in feeders ; yet the carnivorous dog has which they are eaten, whether as less fibrine when fed on vegetable white of egg, fibrine, caseine, or glufood than when bis diet has been ten, they are all reduced by the diexclusively animal. Finally, although gestive process to substances named
LIEBIG : Animal Chemistry, p. 52. + Brande's Chemistry, quoted by PEREIRA. On this subject see the chapter “ The Bread we Eat," in Johnston's Chemistry of Common Life.
peptones, under which forms only make four oxen yield the alimentary are they assimilable.
value of five, as usually employed. Gelatine.—There is perhaps no sub- Great was the excitement, vast stance on our list which more inter- the preparations. In hospitals and estingly illustrates the want of a poorhouses machines were erected true scientific doctrine presiding over which made an enormous quantity the investigations into Food than of Gelatine. Unfortunately the Gelatine: : a substance richer in nitro- soup thus obtained was found far gen than any of the albuminous sub- from nutritious; moreover,
it occastances, yet denied a place among the sioned thirst, digestive troubles, and plastic elements : a substance which, finally diarrhea. The savans heard under the forms of jellies and soups, this with equanimity. They were is largely given to convalescents, who not the men to give up a theory on get strong upon it, yet which, we are the bidding of vulgar experience. emphatically assured, has no nutri- Diarrhea was doubtless distressing, tive value whatever. Mulder says but science was not implicated in that no physician, who has had ex- that. The fault must lie in the preperience, could doubt the nutritive paration of the soup; perhaps the value of gelatine ; and we may be fault was attributable to the souppretty sure that common usage, in eaters : one thing only was positive such cases, is founded upon some -that the fault was not in the Gelasolid ground, and that no substance tine. In this high and unshaken conis largely used as food which has not fidence, the savans pursued their a nutritive value. Common usage; course. Thousands of rations were or what is called “
common sense, daily distributed; but fortunately must not indeed be the arbiter of these rations were not confined to a scientific question ; but it has a the bone-soup, or else the mortalright to be heard, when it unequivo- ity would have been terrific. Few cally contradicts the conclusions of men of science had any doubts until Science; and it can only be put out M. Donné positively assured the Acasfucourt feita clear expositieneésehe demon that experimeen the landi heimself
dogs, proved Gelatine, thus case, Science pretends that Gelatine prepared, to be scarcely, if at all, nucannot be nutritive, common sense tritious. He found that employing asserts that it does nourish ; and un- a notable quantity in his own diet less the fact can be proved against caused him rapidly to lose weight, common sense, it will be reasonable and that during the whole experito suppose that Science is arguing on ment he was tormented with hunger false premises. False, indeed, are and occasional faintness. A cup of the premises, and false the conclu- chocolate and two rolls nourished sion. But let us see what has been him more effectually than two litres the course of inquiry.
and a half of bone-soup accompanied In 1682 the celebrated Papin dis- by 80 to 100 grammes of bread.* covered that bones contained organic These statements were confirmed by matter, and he invented a method of other experimenters, and the confiextraction of this matter, which oc- dence in Gelatine was rudely shaken, cupied the chemists and savans in and would have been ignominiously the early days of the French Revolu- overthrown, had not Edwards and tion with the laudable desire of fur- Balzac published their remarkable nishing food to the famished people. memoir (1833), in which experiments A pound of bones was said to yield conducted with great care and scienas much broth as six pounds of beef, tific rigour established the fact that and, with the true fervour of inven- although Gelatine is insufficient to tors, the savans declared bone-soup support life, it has nevertheless nutrito be better than meat-soup. In tive value. Dogs fed on gelatine and 1817, M. D. Arcet applied steam on bread became gradually thinner and a grand scale to the preparation of feebler; but when fed on bread alone, this gelatine from bones, promising to their loss was far more rapid.
A litre is a trifle more than a pint and a half; a gramme is about 154 grains.
At this period it became necessary supported life, failed utterly when to have the question definitively boiled. settled, and the French Academy ap- We call especial attention to the pointed a Commission to report on fact of the very small proportions of it. This is the celebrated “Gelatine Albumen which exist in the bones, Commission” so often referred to. as strikingly confirming our hypoThe report appeared in 1841. It thesis respecting the power of the showed that dogs perished from star- organism to form Albumen for itself, vation in presence of the Gelatine if a small amount be present to act extracted from bones, after having as a sort of leaven. Moleschott also eaten of it only a few times. When, maintains, on other grounds, that instead of this insipid Gelatine, thé Gelatine must be converted into Alagreeable jelly whích pork-butchers bumen, since the amount of Albumen prepare from a decoction of different in bones is in itself utterly insufficient parts of the pig, was given them, they for the demands of the tissues ;* and ate it with relish at first, then ceased, Mulder points to the fact that, when and died on the twentieth day,of inani- an animal is fed on Gelatine, we tion; when bread or meat, in small never find this substance passing quantities, was given, the dogs lived away in the excreta : a sufficient a longer time, but grew gradually proof that it must in some way have thinner, and all finally perished. Å been incorporated with the organstriking difference was observed be- ism, or decomposed in it, to subserve tween bone-soup and meat-soup: the the purposes of nutrition.t animals starved on the first, and Liebig, obliged by evidence to adflourished on the second.
mit some nutritive quality in GelaThe conclusion generally drawn tine, suggests that it is confined to from this Report is, that Gelatine is the formation of the gelatinous tisnot a nutritive substance. But all
This is one of those hypothat is really proved by the experi- theses which seduce by their plausiments is that Gelatine alone is in- bility, and accordingly it has been sufficient for nutrition ; a conclusion generally adopted, although physiowhich is equally true of albumen, logical scrutiny detects that this is fiborine, for any other single substance precisely one of the muses. to which Ghe
nutrition latine can turnedFor on a mixture of inorganic and organic one hand we see that the herbivora substances, salts, fats, sugars, and have gelatinous tissues, although they albuminates.
eat no Gelatine ; and, on the other When animals are fed on albumen hand, we see that even the carnivora, alone, or white of egg alone, with who do obtain it in their ordinary water as the single inorganic ele- food, cannot form their gelatinous ment, they perish ; but they live tissues out of it, because it is never perfectly well on raw bones and in their blood, from which all the water-the reason being that bones tissues are formed. contain salts and small proportions Bernard has shown that part of of albumen and fats to supplement the Gelatine is converted into sugar, the Gelatine, and they contain these and sugar, we know, is necessary to in the state of organic combination, theorganism. It may also be converted not in the state of chemical products into fat; and, as has been said, there The paramount importance of this is much evidence to show that it may last condition may be gathered from be converted into Albumen among the experiments mentioned in the the complex processes of vital chemGelatine Report-namely, that boil- istry ; but whatever. may be the deing the bones, or digesting them in cision respecting the point, there can hydrochloric acid, and thus resolving be no legitimate reason for denying their cartilaginous tissue into Gela- that Gelatine ranks among nutritive tine, destroyed this nutritive quality. principles. The very bones which, when raw, Fats and Oils. These are various
* MOLESCHOTT, Kreislauf des Lebens, p. 135.
+ MULDER, p. 937.
and important, including suet, lard, and so absorbed. Thus we eat olive marrow, butter, and fixed oils. Vege- oil with salad, or butter with bread, tables also yield a great variety of and the greater part is absorbed ; oils, fixed and volatile, or essential. but the same amount of olive oil The quantity procurable from 100 administered alone would act as a parts of vegetable and animal sub- purge. It is owing, moreover, to the stances is as follows :
minute state of subdivision and
mixture of the oils in all vegetable Filberts,
substances that they are so much Olive seeds,
more digestible than animal fats. Cocoa-nut,
Dr Pereira quotes the statement of Almonds, White mustard,
Dr Beaumont, that "bile is seldom Linseed,
22 found in the stomach, except under Maize,
peculiar circumstances. I have obYolk of eggs,
served that when the use of fat or Ordinary meat,
14. 3 oily food has been persevered in for Caviare,
4. 3 some time, there is generally a preOx-liver,
3.89 sence of bile in the gastric fluids.” Milk, Cows',
Upon which Dr Pereira remarks that Women's,
the popular notion of oily or fatty Asses',
foods “causing bile” is not so groundGoats',
less as medical men have generally Ewes',
4.20 Bones of sheep's feet,
5.55 supposed. The reason of fat being of ox-head,
indigestible is thus suggested :Fats and oils are all difficult of does not become properly chymified. It
“In many dyspeptic individuals, fat digestion--more so, indeed, than most
floats on the contents of the stomach in other principles ; but the degree in the form of an oily pellicle, becoming which they are digestible is very odorous, and sometimes highly rancid, much a matter of individual peculi- and in this state excites heartburn, arity, some men digesting large quan- nausea, and eructations, or at times actities with ease, others being unable tual vomiting. It appears to me that to digest even small quantities. M. the greater tendency which some oily Berthé instituted an elaborate series substances have than others to disturb of experiments on his own person,
the stomach, depends on the greater with the view of ascertaining the facility with which they evolve volatile
fatty acids, which are for the most part comparative digestibility of various exceedingly acrid and irritating.
The fats and oils. The following classi- unpleasant and distressing feelings exfication of his results is all we can
cited in many dyspeptics by the ingesfind space for. First class, com- tion of mutton-fat, butter, and fish-oils prising those difficult of digestion : are in this way readily accounted for, Olive oil, almond oil, poppy-seed oil
since all these substances contain each Second class, comprising those easy
one or more volatile acids to which they of digestion: Whale oil, butter and
owe their odour. Thus mutton-fat conanimal fats, colourless liver-oil. Third
tains hircic acid ; butter, no less than class, comprising those very easy of three volatile acids, viz. butyric, capric, digestion : Pure liver-oil.
and caproic acids; while train-oil conIt should be remembered that great
tains phocenic acid.” I differences are observable according The effect of a high temperature on to the state in which oils are ingested. fat is to render it still more unsuitIf taken by, themselves, they are able to the stomach ; and all persons scarcely affected by the digestive troubled with an awful consciousness process, and act as laxatives ; but if of what digestion is, and not living in taken mingled with other substances, that happy eupeptic ignorance which they may be reduced to an emulsion, only knows digestion by name, should
* PEREIRA : Treatise on Diet, p. 167.
+ BERTHÉ: Moniteur des Hôpitaux, 1856, No. 69. Cannstatt : Jahresbericht 1856, pp. 69-72.
# PEREIRA, p. 171.