The Chemistry of Food and Nutrition - A. W. Duncan (latest books to read .TXT) 📗

known that the over-fed and badly fed are the most irritable and discontented Those living on a stimulating dietary consisting largely of flesh have their chief successes in feats of short duration. Simple and abstemious living individuals or races excel in laborious work requiring endurance over long periods, such as long walking, cycling, and other athletic feats and long military campaigns.

The digestive and assimilative organs need the food constituents of which we have written, in proper proportion and quantity, and in a fairly digestible condition. Within these very wide and comprehensive limits, the organs can be trained. Very much of the great difference in food is due to the non-essential flavouring and stimulating part, rather than to that part which is essential and nourishing. What is the best, interests but few; whilst what is at present the pleasantest, influences the many. The ego, the superphysical conscious and reasoning entity should rule its material body, its temporary vehicle. The body, being the servant of the ego, just as a horse, dog, or other of the lower animals recognises its master, becomes a docile subject. The body can be led into good habits nearly as easily as into bad ones; often more easily, as bad habits are sometimes painfully acquired. The body being once habituated to certain movements, conditions, foods or drinks, within reasonable limits, derives pleasure therefrom and resists change. It is only when the food, etc., transgresses certain elementary principles, that the result is more or less painful. We may on scientific principles condemn flesh-foods, stimulants and elaborately prepared foods; but after ruling all this out, there is still left a very great variety of foods and methods of preparing them: hereon each individual must form his own opinion. Of the foods thus left, the same kind is not equally suitable to everyone, nor even to the same person at different periods.

A delicately balanced, fine-grained, high-toned mind and body responds to every tender influence, and is painfully jarred by that which is coarse. To such, fruits and delicately flavoured and easily digested foods are doubtless best and conducive to purity and clearness of thought. A coarse-grained, badly poised, roughly working body and spirit, is non-responsive except to loud or coarse impulses; and such a one's appetite is gratified, not by simple but by coarsely seasoned foods.

A person who is accustomed to a stimulating dietary of flesh-foods, especially if well-seasoned, finds a simple diet unsatisfying. Should such persons dine off simple vegetarian food, there is a tendency to over-eating. The less stimulating food fails to rouse the digestive organs and to appease the appetite; although an ample supply of nourishment be consumed. This is the reason why so many imagine that it is necessary to eat a larger quantity of food if it be vegetable. Should a distressing fulness and flatulence result from their over-feeding, they lay the blame to the vegetarian dietary instead of to themselves. Most persons, on changing to a vegetarian dietary, commence by imitating flesh dishes in appearance and flavour and even in the names. There is the additional inducement that the food may be attractive and palatable to friends who lack sympathy with the aesthetic and humane principles of the diet. After a while many of them incline to simpler flavoured foods. They revert to the unperverted taste of childhood, for children love sweets, fruits, and mild-flavoured foods rather than savouries. One who loves savouries, as a rule, cares much less for fruits. By compounding and cooking, a very great variety of foods can be prepared, but the differences in taste are much less than is usually, supposed. The effect of seasoning instead of increasing the range, diminishes it, by dulling the finer perception of flavours. The predominating seasoning also obscures everything else. The mixture of foods produces a conglomeration of tastes in which any particular or distinct flavours are obscured, resulting in a general sameness. It is often stated that as an ordinary flesh-eater has the choice of a greater range of foods and flavours than a vegetarian, he can obtain more enjoyment, and that the latter is disagreeably restricted. Certainly he has the choice, but does he avail himself of it to any considerable extent? No one cares to take all the different kinds of food, whether of animal or vegetable that are possible. Of edible animals but a very few kinds are eaten. A person who particularly relishes and partakes largely of flesh-foods will reject as insipid and unsatisfying many mild-flavoured foods at one end of the scale. The vegetarian may abstain from foods at the opposite end of the scale, not always from humane reasons, but because they are unpleasant. Thus there may be little to choose between the mere range of flavours that give enjoyment to each class of persons. The sense of taste is in its character and range lower than the sense of sight and hearing. The cultivation of the taste for savouries seems to blunt the taste for fruits and the delicate foods. The grass and herbs on which the herbivora subsist, seems to our imagination of little flavour and monotonous; but they eat with every sign of enjoyment, deliberately munching their food as though to get its full flavour. In all probability they find a considerable range of flavours in the great varieties of grasses commonly found together in a pasture.

Our elaborate cooking customs entail a vast amount of labour. They necessitate the cost, trouble and dirt from having fires in great excess of that required for warmth: the extra time in preparing, mixing and attending to food which has to be cooked: and the large number of greasy and soiled utensils which have to be cleaned. Cooked savoury food is generally much nicer eaten hot, and this necessitates fires and attention just previous to the meal. We have already said that soft cooked food discourages mastication and leads to defective teeth. Our elaborate cookery is mainly due to our custom of eating so largely of flesh, whilst the eating of flesh would receive a great impetus on the discovery of the art of cooking. Flesh can only be eaten with relish and with safety when cooked. Such a large proportion of it is infected with parasites, or is otherwise diseased, that it would he dangerous to eat it raw, even were it palatable in such a state. In those countries where man eats flesh in a raw or semi-cooked form, parasitic diseases are common. There is not the least doubt that our habit of eating so much cooked food is responsible for much over-eating, hasty eating, dyspepsia and illness. In regard to the making of bread, porridge, and many other comparatively simple prepared foods, the advantages of cooking seem overwhelmingly great. With our present imperfect knowledge and conflicting opinions, it is impossible to arrive at any satisfactory conclusion, and the whole question requires careful and impartial investigation. Experiments have been made with animals, chiefly pigs, with cooked and uncooked clover, hay, corn, meal, etc. (U.S. Department of Agriculture). It was found that the food was more or less diminished in digestibility by cooking. At least 13 separate series of experiments with pigs in different part of the country have been reported. In 10 of these trials there has been a positive loss from cooking the food. The amount of food required to produce in the animal a pound gain in weight was larger when the food had been cooked than when it was given raw. In some cases, the increased quantity of food required after cooking was considerable.

Those who live on uncooked food contend that a smaller quantity of nourishment is required. As uncooked food requires more mastication and is eaten more slowly, there is a better flow of saliva and time is given for the digestive organs to be gradually brought into complete action, and finally for the appeasing of the appetite. In the case of the members of the fruitarian family, whose food was uncooked, and of whom we have previously written, the quantity of nutriment taken was much less than that thought necessary, even after making full allowance for their small stature and weight.

Meat Extracts.—Justus von Liebig, the great German chemist, was the first to attempt to make these on the commercial scale. He described a method in 1847, and this not proving satisfactory, another one in 1865. He stated that the only practicable plan on a manufacturing scale, was to treat the chopped flesh with eight to ten times its weight of water, which was to be raised to 180° F. In another passage he says it is to be boiled for half-an-hour. After straining from all the undissolved meat fibre, etc., and carefully cleansing from all fat, the decoction is to be evaporated to a soft extract; such a preparation is practically free from albumin, gelatin and fat; all the nutritive principles except the saline matter having been extracted. Liebig states that 34 pounds of meat are required to produce 1 pound of extract. In 1872, he wrote "neither tea nor extract of meat are nutritive in the ordinary sense," and he went on to speak of their medicinal properties. Druit, in 1861, in describing the effect of a liquid preparation of meat, states that it exerted a rapid and stimulating action on the brain, and he proposed it as an auxiliary and partial substitute for brandy, in all case of great exhaustion or weakness attended with cerebral depression or despondency. In like manner, a feast of animal food in savages, whose customary diet was almost exclusively vegetable, has been described by travellers as producing great excitement and stimulation similar to that of intoxicating spirits. Similar effects have been observed from a copious employment of Liebig's extract. Voit asserts, from the results of his experiments, that extract of meat is practically useless as a food, and other authorities are quite of the same opinion, although they may value it as a stimulant and drug. _The Extra Pharmacopæia_, 1901, states that "Liebig's Extract or Lemco consists of creatin, creatinin, globulin and urea, with organic potash and other salts. It has been much over-estimated as a food either for invalids or healthy persons; still it is often valuable as a flavouring to add to soups, beef-tea, etc., and it is a nerve food allied to tea." Meat extracts stimulate the action of the heart and the digestive processes, but as in the case of other stimulants there is a succeeding period of depression. The British Medical Journal says that the widespread belief in the universal suitability of concentrated beef-tea is frequently responsible for increasing the patient's discomfort, and is even capable in conditions of kidney inefficiency, of producing positive harm. Some of the meat bases, the leucomaines, have been found to possess marked poisonous effects on the body. The manfacturers of meat extracts continue to mislead the public by absurdly false statements of the value of their products. They assert that their extracts contain the nutritive matter of 30, 40 or 50 times their weight of fresh meat, or that one or two meat-lozenges are sufficient for a meal. One company, asserts by direct statement, or imply by pictorial advertisement, that the nutritive matter in an ox can be concentrated into the bulk of a bottle of extract; and another company that a tea-cup full is equivalent in food value to an ox. Professor Halliburton writes: "Instead of an ox in a tea-cup, the ox's urine in a tea-cup would be much nearer the fact, for the meat extract consists largely of products on the way to urea, which more nearly resemble in constitution the urine than they do the flesh of the ox." Professor Robert Bartholow has also stated that the chemical composition of beef-tea closely resembles urine, and is more an excrementitious substance than a food. Those whose business it is to make a pure meat-broth, for the purpose of preparing therefrom a nutrient for experimenting with bacteria, cannot fail to