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Science in the Kitchen – Food

A picture for the book Science in the Kitchen

The purposes of food are to promote growth, to supply force and heat, and to furnish material to repair the waste which is constantly taking place in the body. Every breath, every thought, every motion, wears out some portion of the delicate and wonderful house in which we live. Various vital processes remove these worn and useless particles; and to keep the body in health, their loss must be made good by constantly renewed supplies of material properly adapted to replenish the worn and impaired tissues. This renovating material must be supplied through the medium of food and drink, and the best food is that by which the desired end may be most readily and perfectly attained. The great diversity in character of the several tissues of the body, makes it necessary that food should contain a variety of elements, in order that each part may be properly nourished and replenished.

The Food Elements.—The various elements found in food are the following: Starch, sugar, fats, albumen, mineral substances, indigestible substances.

The digestible food elements are often grouped, according to their chemical composition, into three classes; vis., carbonaceous, nitrogenous, and inorganic. The carbonaceous class includes starch, sugar, and fats; the nitrogenous, all albuminous elements; and the inorganic comprises the mineral elements.

Starch is only found in vegetable foods; all grains, most vegetables, and some fruits, contain starch in abundance. Several kinds of sugar are made in nature’s laboratory; cane, grape, fruit, and milk sugar. The first is obtained from the sugar-cane, the sap of maple trees, and from the beet root. Grape and fruit sugars are found in most fruits and in honey. Milk sugar is one of the constituents of milk. Glucose, an artificial sugar resembling grape sugar, is now largely manufactured by subjecting the starch of corn or potatoes to a chemical process; but it lacks the sweetness of natural sugars, and is by no means a proper substitute for them. Albumen is found in its purest, uncombined state in the white of an egg, which is almost wholly composed of albumen. It exists, combined with other food elements, in many other foods, both animal and vegetable. It is found abundant in oatmeal, and to some extent in the other grains, and in the juices of vegetables. All natural foods contain elements which in many respects resemble albumen, and are so closely allied to it that for convenience they are usually classified under the general name of “albumen.” The chief of these is gluten, which is found in wheat, rye, and barley. Casein, found in peas, beans, and milk, and the fibrin of flesh, are elements of this class.

Fats are found in both animal and vegetable foods. Of animal fats, butter and suet are common examples. In vegetable form, fat is abundant in nuts, peas, beans, in various of the grains, and in a few fruits, as the olive. As furnished by nature in nuts, legumes, grains, fruits, and milk, this element is always found in a state of fine subdivision, which condition is the one best adapted to its digestion. As most commonly used, in the form of free fats, as butter, lard, etc., it is not only difficult of digestion itself, but often interferes with the digestion of the other food elements which are mixed with it. It was doubtless never intended that fats should be so modified from their natural condition and separated from other food elements as to be used as a separate article of food. The same may be said of the other carbonaceous elements, sugar and starch, neither of which, when used alone, is capable of sustaining life, although when combined in a proper and natural manner with other food elements, they perform a most important part in the nutrition of the body. Most foods contain a percentage of the mineral elements. Grains and milk furnish these elements in abundance. The cellulose, or woody tissue, of vegetables, and the bran of wheat, are examples of indigestible elements, which although they cannot be converted into blood in tissue, serve an important purpose by giving bulk to the food.

With the exception of gluten, none of the food elements, when used alone, are capable of supporting life. A true food substance contains some of all the food elements, the amount of each varying in different foods.

Uses of the Food Elements.—Concerning the purpose which these different elements serve, it has been demonstrated by the experiments of eminent physiologists that the carbonaceous elements, which in general comprise the greater bulk of the food, serve three purposes in the body;

1. They furnish material for the production of heat;

2. They are a source of force when taken in connection with other food elements;

3. They replenish the fatty tissues of the body. Of the carbonaceous elements,—starch, sugar, and fats,—fats produce the greatest amount of heat in proportion to quantity; that is, more heat is developed from a pound of fat than from an equal weight of sugar or starch; but this apparent advantage is more than counterbalanced by the fact that fats are much more difficult of digestion than are the other carbonaceous elements, and if relied upon to furnish adequate material for bodily heat, would be productive of much mischief in overtaxing and producing disease of the digestive organs. The fact that nature has made a much more ample provision of starch and sugars than of fats in man’s natural diet, would seem to indicate that they were intended to be the chief source of carbonaceous food; nevertheless, fats, when taken in such proportion as nature supplies them, are necessary and important food elements.

The nitrogenous food elements especially nourish the brain, nerves, muscles, and all the more highly vitalized and active tissues of the body, and also serve as a stimulus to tissue change. Hence it may be said that a food deficient in these elements is a particularly poor food.

The inorganic elements, chief of which are the phosphates, in the carbonates of potash, soda, and lime, aid in furnishing the requisite building material for bones and nerves.

Proper Combinations of Foods.—While it is important that our food should contain some of all the various food elements, experiments upon both animals and human beings show it is necessary that these elements, especially the nitrogenous and carbonaceous, be used in certain definite proportions, as the system is only able to appropriate a certain amount of each; and all excess, especially of nitrogenous elements, is not only useless, but even injurious, since to rid the system of the surplus imposes an additional task upon the digestive and excretory organs. The relative proportion of these elements necessary to constitute a food which perfectly meets the requirements of the system, is six of carbonaceous to one of nitrogenous. Scientists have devoted much careful study and experimentation to the determination of the quantities of each of the food elements required for the daily nourishment of individuals under the varying conditions of life, and it has come to be commonly accepted that of the nitrogenous material which should constitute one sixth of the nutrients taken, about three ounces is all that can be made use of in twenty-four hours, by a healthy adult of average weight, doing a moderate amount of work. Many articles of food are, however, deficient in one or the other of these elements, and need to be supplemented by other articles containing the deficient element in superabundance, since to employ a dietary in which any one of the nutritive elements is lacking, although in bulk it may be all the digestive organs can manage, is really starvation, and will in time occasion serious results.

It is thus apparent that much care should be exercised in the selection and combination of food materials. The table on page 484, showing the nutritive values of various foods, should be carefully studied. Such knowledge is of first importance in the education of cooks and housekeepers, since to them falls the selection of the food for the daily needs of the household; and they should not only understand what foods are best suited to supply these needs, but how to combine them in accordance with physiological laws.

Condiments.—By condiments are commonly meant such substances as are added to season food, to give it “a relish” or to stimulate appetite, but which in themselves possess no real food value. To this category belong mustard, ginger, pepper, pepper sauce, Worcestershire sauce, cloves, spices, and other similar substances. That anything is needed to disguise or improve the natural flavor of food, would seem to imply either that the article used was not a proper alimentary substance, or that it did not answer the purpose for which the Creator designed it. True condiments, such as pepper, pepper sauce, ginger, spice, mustard, cinnamon, cloves, etc., are all strong irritants. This may be readily demonstrated by their application to a raw surface. The intense smarting and burning occasioned are ample evidence of the irritating character. Pepper and mustard are capable of producing powerfully irritating effects, even when applied to the healthy skin where wholly intact. It is surprising that it does not occur to the mother who applies a mustard plaster to the feet of her child, to relieve congestion of the brain, that an article which is capable of producing a blister upon the external covering of the body, is quite as capable of producing similar effects when applied to the more sensitive tissues within the body. The irritating effects of these substances upon the stomach are not readily recognized, simply because the stomach is supplied with very few nerves of sensation. That condiments induce an intense degree of irritation of the mucous membrane of the stomach, was abundantly demonstrated by the experiments of Dr. Beaumont upon the unfortunate Alexis St. Martin. Dr. Beaumont records that when St. Martin took mustard, pepper, and similar condiments with his food, the mucous membrane of his stomach became intensely red and congested, appearing very much like an inflamed eye. It is this irritating effect of condiments which gives occasion for their extended use. They create an artificial appetite, similar to the incessant craving of the chronic dyspeptic, whose irritable stomach is seldom satisfied. This fact with regard to condiments is a sufficient argument against their use, being one of the greatest causes of gluttony, since they remove the sense of satiety by which Nature says, “Enough.”

To a thoroughly normal and unperverted taste, irritating condiments of all sorts are very obnoxious. It is true that Nature accommodates herself to their use with food to such a degree that they may be employed for years without apparently producing very grave results; but this very condition is a source of injury, since it is nothing more nor less than the going to sleep of the sentinels which nature has posted at the portal of the body, for the purpose of giving warning of danger. The nerves of sensibility have become benumbed to such a degree that they no longer offer remonstrance against irritating substances, and allow the enemy to enter into the citadel of life. The mischievous work is thus insidiously carried on year after year until by and by the individual breaks down with some chronic disorder of the liver, kidneys, or some other important internal organ. Physicians have long observed that in tropical countries where curry powder and other condiments are very extensively used, diseases of the liver, especially acute congestion and inflammation, are exceedingly common, much more so that in countries and among nations where condiments are less freely used. A traveler in Mexico, some time ago, described a favorite Mexican dish as composed of layers of the following ingredients: “Pepper, mustard, ginger, pepper, potato, ginger; mustard, pepper, potato, mustard, ginger, pepper.” The common use of such a dish is sufficient cause for the great frequency of diseases of the liver among the Mexicans, noted by physicians traveling in that country. That the use of condiments is wholly a matter of habit is evident from the fact that different nations employ as condiments articles which would be in the highest degree obnoxious to people of other countries. For example, the garlic so freely used in Russian cookery, would be considered by Americans no addition to the natural flavors of food; and still more distasteful would be the asafetida frequently used as a seasoning in the cuisine of Persia and other Asiatic countries.

The use of condiments is unquestionably a strong auxiliary to the formation of a habit of using intoxicating drinks. Persons addicted to the use of intoxicating liquors are, as a rule, fond of stimulating and highly seasoned foods; and although the converse is not always true, yet it is apparent to every thoughtful person, that the use of a diet composed of highly seasoned and irritating food, institutes the conditions necessary for the acquirement of a taste for intoxicating liquors. The false appetite aroused by the use of food that “burns and stings,” craves something less insipid than pure cold water to keep up the fever the food has excited. Again, condiments, like all other stimulants, must be continually increased in quantity, or their effect becomes diminished; and this leads directly to a demand for stronger stimulants, both in eating and drinking, until the probable tendency is toward the dram-shop.

A more serious reason why high seasonings leads to intemperance, is in the perversion of the use of the sense of taste. Certain senses are given us to add to our pleasure as well as for the practical, almost indispensable, use they are to us. For instance, the sense of sight is not only useful, but enables us to drink in beauty, if among beautiful surroundings, without doing us any harm. The same of music and other harmonics which may come to us through the sense of hearing. But the sense of taste and was given us to distinguish between wholesome and unwholesome foods, and cannot be used for merely sensuous gratification, without debasing and making of it a gross thing. An education which demands special enjoyment or pleasure through the sense of taste, is wholly artificial; it is coming down to the animal plane, or below it rather; for the instinct of the brute creation teaches it merely to eat to live.

Yet how wide-spread is this habit of sensuous gratification through the sense of taste! If one calls upon a neighbor, he is at once offered refreshments of some kind, as though the greatest blessing of life came from indulging the appetite. This evil is largely due to wrong education, which begins with childhood. When Johnnie sits down to the table, the mother says, “Johnnie, what would you like?” instead of putting plain, wholesome food before the child, and taking it as a matter of course that he will eat it and be satisfied. The child grows to think that he must have what he likes, whether it is good for him or not. It is not strange that an appetite thus pampered in childhood becomes uncontrollable at maturity; for the step from gormandizing to intoxication is much shorter than most people imagine. The natural, unperverted taste of a child will lead him to eat that which is good for him. But how can we expect the children to reform when the parents continually set them bad examples in the matter of eating and drinking?

The cultivation of a taste for spices is a degradation of the sense of taste. Nature never designed that pleasure should be divorced from use. The effects of gratifying the sense of taste differ materially from those of gratifying the higher senses of sight and hearing. What we see is gone; nothing remains but the memory, and the same is true of the sweetest sounds which may reach us through the ears. But what we taste is taken into the stomach and what has thus given us brief pleasure through the gratification of the palate, must make work in the alimentary canal for fourteen hours before it is disposed of.

Variety in Food.—Simplicity of diet should be a point of first consideration with all persons upon whom falls the responsibility of providing the family bills of fare, since the simplest foods are, as a rule, the most healthful. Variety is needed; that is, a judicious mingling of fruits, grains, and vegetables; but the general tendency is to supply our tables with too many kinds and to prepare each dish in the most elaborate manner, until, in many households, the cooking of food has come to be almost the chief end of life. While the preparation of food should be looked upon as of so much importance as to demand the most careful consideration and thought as to its suitability, wholesomeness, nutritive qualities, and digestibility, it should by no means be made to usurp the larger share of one’s time, when simpler foods and less labor would afford the partakers equal nourishment and strength.

A great variety of foods at one meal exerts a potent influence in creating a love of eating, and is likewise a constant temptation to overeat. Let us have well-cooked, nutritious, and palatable food, and plenty of it; variety from day to day, but not too great a variety at each meal.

The prevalent custom of loading the table with a great number of viands, upon occasions when guests are to be entertained in our homes, is one to be deplored, since it is neither conducive to good health nor necessary to good cheer, but on the contrary is still laborious and expensive a practice that many are debarred from social intercourse because they cannot afford to entertain after the fashion of their neighbors. Upon this subject a well-known writer has aptly said: “Simplify cookery, thus reducing the cost of living, and how many longing individuals would thereby be enabled to afford themselves the pleasure of culture and social intercourse! When the barbarous practice of stuffing one’s guests shall have been abolished, a social gathering will not then imply, as it does now, hard labor, expensive outlay, and dyspepsia. Perhaps when that time arise, we shall be sufficiently civilized to demand pleasures of a higher sort. True, the entertainments will then, in one sense, be more costly, as culture is harder to come by than cake. The profusion of viands now heaped upon the table, betrays poverty of the worst sort. Having nothing better to offer, we offer victuals; and this we do with something of that complacent, satisfied air with which some more northern tribes present their tidbits of whale and walrus.”