Hygiene: a manual of personal and public health (New Edition)
CHAPTER VII.
CONDIMENTS AND BEVERAGES.
CONDIMENTS, ETC.—The name condiment is used in various senses by different writers. In its strictest sense it is a substance containing a volatile oil or ether, which may be taken with salt, and the object of which is to excite the senses of taste and smell, and consequently produce an appetising effect. This definition excludes _spices_, substances allied to condiments, but usually taken with sugar, as cinnamon, ginger, etc.; also _flavouring agents_, such as vanilla; and _acids_, such as vinegar and lemon-juice. If we use the word in its widest sense, to include these various groups of substances, we find that all condiments are taken with the object of improving the taste or flavour of food, or of assisting its digestion; but that they are not foods in the sense of supplying any elements towards building up the body or maintaining its heat. The only partial exception is lemon-juice, the salts of which have a quasi-medicinal use.
Taste is usually a compound sensation, the organs of which are the nerves of taste and smell. True taste is confined to the appreciation of sensations of bitter and sweet; but the flavour of meats is nearly entirely appreciated by the sense of smell. This is shown by the fact that meats appear tasteless and insipid, during “a cold in the head.” In the appreciation of acid, astringent, and fiery substances, the sense of touch is also employed. The excitement of these different nerves results in a stimulus which is carried up to the central nervous system, and causes by reflex action an increased flow of the digestive juices. Hot substances, like cayenne and ginger, also cause an increased flow of gastric juice, by directly congesting the mucous membrane. This action is not so desirable as that through the influence of the nervous system. All natural foods are sapid and possessed of flavour, and thus stimulate secretion; but any local irritating effect ought to be avoided.
1. =Condiments= proper comprise chiefly mustard, pepper, cayenne, garlic, onion, capers, mint, sage, morels, mushrooms, truffles. The last three on the list are also foods, but are more commonly used as condiments.
All these act as stimulants to the digestive organs, and in small quantities aid digestion. The active principle of mustard and horse-radish is sulphocyanide of allyl. Horse-radish is not so wholesome as mustard, the scraped root being apt to adhere to the stomach like the skins of grapes, and produce indigestion. Pepper contains an acrid resin, a volatile oil, and an alkaloidal substance, called piperine. Cayenne contains an analogous substance, called capsicin. Cayenne, unless in extreme moderation, is harmful, as its small particles adhere to the mucous membrane of the stomach, and may set up considerable irritation.
2. =Spices= are those condiments which contain an aromatic oil, and which harmonize with sugar. They are, as a rule, less irritating to the stomach than those of the pepper group. Cinnamon, cloves, camphor, ginger, and curry powder are the chief of these. Curry powder really belongs to both the first and second divisions. When genuine, it is said to contain turmeric, cardamoms, ginger, allspice, cloves, black pepper, coriander, cayenne, and a few other substances.
3. =Flavouring agents=, such as vanilla, lemon peel, and fruit essences, are used to give a pleasant flavour to various dishes.
4. =Acidulous substances= are taken chiefly because of their sharp and agreeable taste. Vinegar is the chief acid employed. It is produced by the action of a fungus (_Mycoderma aceti_) on alcoholic liquids, as wine, or beer, C₂H₅OH (alcohol) becoming C₂H₄O₂ (acetic acid). It is also produced by the destructive distillation of wood. In small quantities it does not stop digestion, but, by exciting the nerves of taste, may be of actual service. It helps to soften the vegetable fibres in a salad; and is also useful for the same purpose with hard meats, as lobster, etc. In large quantities it diminishes the power to assimilate food.
Good vinegar ought not to contain less than 3 per cent. of acetic acid; and sulphuric acid beyond 1 in 1000 in vinegar is to be regarded as an adulteration. A specific gravity below 1015 indicates the addition of water.
Citric acid and lemon-juice are useful for their refreshing properties, and the latter also because of its alkaline salts.
=Oils=, such as olive oil, have been sometimes classed under condiments, but as they have great nutritive properties, this is hardly accurate. For the same reason, =salt= is not classed under this head.
BEVERAGES.
Water is the universal beverage, and for healthy persons is preferable to any other. All other beverages necessarily contain it as their basis.
It will be convenient to consider first aërated and other natural waters; then tea, coffee, and cocoa; and finally, alcohol.
=1. Aerated Waters= contain carbonic acid (carbon dioxide) in solution, which gives to them their characteristic sharp taste and sparkling character. Thus distilled water charged with gas is sold as Salutaris or Puralis water. Soda water contains three to five grains, and medicinal soda water fifteen grains of bicarbonate of soda to the bottle. Potash water contains fifteen grains of bicarbonate of potash to the pint, in each case carbonic acid being dissolved under pressure. In lemonade, ginger-beer, etc., the basis is sweetened water, rendered tart by the addition of an acid, and finally charged with carbonic acid. Lemonade frequently contains acetic or phosphoric acid instead of citric or tartaric, and ginger-beer the same constituents with some added tincture of ginger. Home-made lemonade prepared from fresh lemons is a much more wholesome drink. Ginger-beer (stone ginger) is produced by the fermentative action of yeast on a solution containing sugar, bruised ginger, tartaric acid, and oil of lemon. It usually contains at least two per cent. of alcohol.
=Natural Mineral Waters= usually contain common salt (chloride of sodium) and alkaline salts of soda or lime, and are impregnated with carbonic acid gas. Apollinaris, Rosbach, and Johannis possess these characteristics. The carbonic acid in natural waters is partially combined, and is given off more gradually than that in artificial mineral waters.
In all the preceding waters there is considerable carbonic acid. This acts as a sedative to the mucous membrane of the stomach, and is useful in indigestion. An aërated water added to milk renders it more digestible by diluting it, and by preventing the formation in the stomach of a heavy clot of casein. In the making of artificial aërated waters, it is essential that the water employed should be pure, that the acid used in generating the carbonic acid should be free from arsenic or other impurities, and that the water should not be allowed to come into contact with lead at any stage, as in pewter fittings. One per cent. of proof spirit is allowed in temperance beverages by the Excise.
TEA.
Tea is the leaf of an evergreen shrub, the _Camellia thea_, which is cultivated in China, Japan, British India, Ceylon, Java, and other countries. The tea leaves, as seen in this country, uncurl in hot water. They are lanceolated, with a serrated edge, and the veins do not extend to the edge of each leaf. By these characteristics they may be distinguished from foreign leaves, _e.g._, the sloe and willow used as adulterants (Fig. 4). The use of old and exhausted leaves can be detected by a determination of the percentage of soluble matter dissolved by boiling water from a given weight of tea. This on evaporation to dryness should be 28 to 30 per cent. of the total weight of the original tea. The presence of clay, iron dust or other forms of dust is detected by igniting a given amount of tea and determining the amount of ash. This should be only about six per cent.
In _black tea_, the leaves are dried in the sun, rolled and allowed to become soft and to ferment. During this process, some of the tannin appears to be converted into less soluble forms. The leaves are afterwards sun-dried, and these “fired” in a furnace. _Green tea_ leaves are dried in the fresh condition over wood fires. Indian teas have more “body” and astringency than China teas. The smallest and topmost leaves of the tea plant give the finest sort of tea (Orange Pekoe); next to this comes Pekoe; the next largest leaves producing Souchong; after these Congou; while the coarser leaves nearer the base used to yield Bohea, which is now seldom seen.
Tea consists of three important constituents—volatile oil, theine or caffeine, and tannin—and soluble and insoluble extractive matters.
The amount of caffeine varies from 2 to 4 per cent. „ „ „ tannin „ „ 10 to 12 „ „ „ „ „ volatile oil is about 1∕2 „ „
(1) =Volatile Oil= gives the aroma and flavour to each particular tea. It is this which causes the headache, trembling, wakefulness, and restlessness, occasionally produced by tea, especially by green tea.
(2) =Theine= or =caffeine=, is an alkaloidal crystalline principle. Its composition is represented by the formula C₈H₁₀N₄O₂, H₂O. Ceylon tea, broken leaf contains 4·03 per cent., Assam (Indian) tea, broken leaf 4·02 per cent., while Chinese teas contain from 2·89 (Moyune Gunpowder) to 3·74 (Moning, black leaf) per cent. of caffeine (Allen).
Theine is the most important constituent of tea and coffee. It is a stimulant, but unlike alcohol, acts even more upon the central nervous system than upon the heart. It removes the sense of fatigue, and may, especially if taken in excessive doses, produce sleeplessness. Its stimulant action on the heart is followed by increased flow of urine, and it thus helps in the removal of waste products from the system. The effect on the tissue-changes of the body is somewhat doubtful. It has been stated to arrest or diminish the waste, _i.e._, the metabolism, constantly going on in the system, and so diminish the amount of food required to repair this waste. This is highly improbable; we cannot conceive the likelihood of the development of energy without a corresponding expenditure of material, and that is what would be the case if theine increased the activity of various organs while retarding their waste. The experiments of Conty and Guimarès on the action of coffee show that this (and tea has the same essential constituent) does not diminish tissue waste. It does not prolong life in starvation, though it may lessen the feeling of hunger. Hence tea and coffee, which owe their value mainly to the caffeine or theine contained in them, are in no sense foods.
(3) The amount of _Tannin_ varies from 12·31 in Ceylon tea (broken leaf, Pekoe) to 11·76 in Moning, black leaf, and 9·9 per cent. in Natal Pekoe Souchong (Allen). The difference in tannin between Chinese and Indian teas is not therefore so great as is usually supposed. Tannin is a powerful astringent, and possesses a bitter styptic taste, and a constipating effect on the bowels. Its amount is increased by long “brewing,” as is shown by the following results (Hale White):—
_Three Minutes’ _Fifteen Minutes’ Infusion._ Infusion._
Finest Assam 11·30 per cent. 17·73 per cent. „ China 7·77 „ „ 7·97 „ „ Common Congou 9·37 „ „ 11·15 „ „
=The Mode of Preparation of Tea= is important. It is clear that the percentage of tannin to weight of leaf used in making the infusion increases with the protraction of the infusion. On the other hand caffeine is so soluble that it is nearly completely dissolved as soon as infusion has begun. Dittmann found that five minutes infusion of Indian tea extracted 3·63 and ten minutes infusion 3·73 per cent. of caffeine. The Chinese put the tea leaves in a cup, and having poured boiling water on them, drink the resulting infusion after a very short time, without adding anything. The Russians drink the infusion with a squeeze of lemon, and with or without sugar. We add cream or milk and generally sugar, and so render it more nutritious, though the delicate flavour is veiled. The Chinese plan of infusion for a short time is the best, as it ensures the extraction of the aromatic and stimulant principles of the tea with only a proportion of the tannin.
In making tea it is important to use a tea-pot which is quite dry, in order to avoid mustiness; to pour a small quantity of boiling water into the tea-pot and then out again, so that the infusion may be made at the temperature of boiling water; and to use water which has only freshly come to the boil, and so has not been rendered flat, and not to infuse longer than five minutes. For persons of weak digestion, the best kind of tea is that obtained by pouring boiling water on the leaves, and then immediately pouring the resulting infusion into another hot tea-pot. In all cases where tea has to be kept a considerable time, it should be poured into a second tea-pot, the leaves being left behind.
Indigestion is not an uncommon consequence of tea-drinking; caused by the excess of tannin in the tea, by the other constituents of the tea, or more commonly by the practice of drinking tea in small sips, with bread and butter. The tea infusion usurps the place of the saliva, the secretion of saliva remaining partially in abeyance. The presence of tannin in tea renders it an undesirable part of a substantial meal. Tannin coagulates albumin, and retards its solution by the digestive juices. Hence “high teas” and “tea-dinners,” unless the tea is very weak, are objectionable. The practice of drinking tea with every meal is inexcusable.
For quenching thirst during active exercise, and rendering possible prolonged exertions, tea is unsurpassed.
COFFEE.
Coffee is the seed of the berry of the _Caffea Arabica_. Each berry contains two seeds, or beans as they are sometimes incorrectly called. The coffee is prepared by roasting the seeds until they assume a reddish-brown colour, in which process they lose 15 per cent. in weight and gain 30 per cent. in bulk. During the process of roasting, a volatile oil having a powerful aromatic smell is developed. This is not produced in such large quantities from fresh seeds; the best time for roasting varying, however, for different varieties of coffee.
The amount of =Volatile Oil= in coffee is much less than in tea. As it is elicited during the process of roasting, this should be done with nicety and care. It is effected in an iron cylinder made to revolve over a fire. After the roasting, the sooner the seeds are ground the better the coffee. When it cannot be immediately used, it should be kept in closed canisters, and not in paper or open jars.
In addition to the volatile oil, which is contained in roasted coffee in the proportion of about 1 part in 50,000, coffee contains =caffeine=, of which there is 3∕4 to 1 per cent., and an =astringent acid=, called caffeo-tannic or caffeic acid, which differs from ordinary =tannin= in that it does not blacken a solution of an iron salt.
The chief adulteration of coffee is =Chicory=, which is thought by some to improve the coffee. It is generally harmless, though in some people it produces heartburn and diarrhœa. Chicory is prepared from the root of the wild endive. It contains a volatile oil and a bitter principle, but no caffeine. It is, therefore, of no utility as a stimulant. Its presence can be detected by shaking a little of the suspected coffee on to the surface of the water in a wine-glassful of cold water. Coffee swims on the surface, and gives little or no colouration to the water; while chicory sinks, and gives a deep red tint. The aqueous extract of pure coffee (extracted by boiling water) is, when evaporated, 25 to 30 per cent. of the weight of the original decoction of coffee; while that of chicory is 65 to 70 per cent.; and on this basis, as well as on the fact that a filtered decoction of 10 grammes of coffee in 100 c.c. of distilled water, cooled to 60° F. has a specific gravity of 1009, while that of a similar solution of chicory would be 1021, the proportion of chicory in a mixture of coffee and chicory can be calculated. The microscopical appearances of the two powders differ, coffee showing hexagonal cells and no laticiferous vessels, unlike chicory. There is no law against selling mixed coffee and chicory, if the fact that it is a mixture is stated; and the proportion of the two unfortunately is not required to be stated. As a pound of coffee costs five times as much as a pound of chicory, it is obviously to the purchaser’s advantage to make his own mixture in the proportions desired.
=The Preparation of Coffee= ought to be effected as in the case of tea—by making an infusion and not a decoction, _i.e._ by pouring boiling water on the coffee and allowing it to stand, but not continuing the boiling. Continuance of boiling dissipates the delicate aroma.
Inasmuch as coffee contains a much smaller percentage of theine than tea, more of the former must be used to obtain a beverage equally refreshing with tea. Two ounces to a pint of boiling water are required. The infusion thus made should be mixed with an equal part of boiled milk. The coffee ought, if possible, to be freshly roasted.
The colour of coffee is no guide to its strength. Many of the black coffees, especially “French coffee,” owe their colour to the caramel (burnt sugar) contained in the chicory mixed with them.
Coffee has similar properties to tea, with some minor differences. (1) Like tea, it is restorative and sustaining in its action, but seems to act more quickly than tea. (2) Unlike tea, it does not tend to produce perspiration, but rather a dry hot skin. (3) With some it is decidedly laxative; while tea, especially if badly made, has an opposite effect; but this is not always true. (4) It seems to have a greater power of antagonising the effects of alcohol than tea; and is a valuable antidote, after the action of an emetic, in poisoning by opium or arsenic or alcohol.
As a rule, coffee is not so prone to disorder the digestion as tea, but this is not universally true, and in some persons it always produces “biliousness.” When taken in excess, it produces—besides indigestion—palpitation, restlessness, irritability, sleeplessness, and a condition of general nervous prostration; in fact, similar symptoms to those produced by a prolonged over-indulgence in tea.
While the consumption of tea is rapidly on the increase, that of coffee is steadily diminishing. This is partly owing to the greater expense of coffee—a larger quantity being required to form a good beverage; and partly to the greater difficulty in preparing good coffee.
COCOA.
Cocoa, or more properly cacao, is obtained from the seeds of the _Theobroma Cacao_—a native of the West Indies, Mexico, and the central parts of America. Its name Theobroma was given it by Linnæus, and means the “food of gods.” The fruit is a large leathery capsule, having nearly the form of a cucumber. It contains from 25 to 30 seeds, each about the size of an almond. Before using, these are roasted like coffee berries, and a peculiar aroma is developed in this process as in the case of coffee. The beans or seeds are then manufactured into three different products. (1) They are simply deprived of their husks and broken to pieces; this forms =Cocoa-Nibs=. (2) They are ground, husk and all, between hot rollers into a paste, and mixed with starch and sugar; this forms =Cocoa=. (3) They are shelled and then ground into a paste, as in making cocoa; sugar and some seasoning, usually vanilla, being subsequently thoroughly mixed; this paste is =Chocolate=.
The purest form is the cocoa-nibs. When these are boiled in water, a brownish decoction is formed, with the fat as a scum at the top; this may be removed, and the decoction flavoured with milk and sugar. In this form, cocoa can be taken by invalids with weak digestion, who would be nauseated by the fat of ordinary cocoa or chocolate.
The best cocoa is prepared as above; but the lowest quality contains the husks of the beans, with hardly any of the beans in it; a somewhat better, though still inferior sort, is made from the smaller fragments of the nibs, and a good deal of husk. In some cases the cacao butter is removed during the process of preparation, and starch or sugar substituted. This form is less likely to disagree with dyspeptics than whole cocoa.
The action of the =Volatile Oil= (not the cacao-butter) developed during roasting, is probably similar to that of tea and coffee, though it is less =in amount=. The bitterness is greater than that of coffee, but the astringency less than in either tea or coffee.
The =Concrete Oil=, or fat of cocoa, forms about half its weight. It is white, and not apt to turn rancid, and possesses an agreeable flavour. Cocoa also contains a certain amount of starch and cellulose.
=Theobromine= is a white crystalline alkaloid, the exact analogue of caffeine. The latter, in fact, is methyl-theobromine—that is, theobromine _plus_ the theoretical group CH₂. Theobromine possesses similar properties to caffeine. It amounts to 1.5 to 2 per cent. of the whole bean. The ordinary preparations of cocoa differ considerably in composition as may be seen from the following table of per centage composition (Ewell). In each instance other nitrogenous and non-nitrogenous constituents go to make up the total 100:
┌───────────────────────────┬──────┬──────┬──────┬──────┬──────────┐ │ │ FAT. │FIBRE.│CANE- │ ASH. │ ADDED │ │ │ │ │SUGAR.│ │ STARCH. │ │ ├──────┼──────┼──────┼──────┼──────────┤ │_Fry’s Cocoa Extract_ │ 30·9 │ 3·9 │ ── │ 4·2 │ None. │ │_Schweitzer’s Cocoatina_ │ 31·1 │ 3·7 │ ── │ 6·3 │ Do. │ │_Rowntree’s Cocoa Extract_ │ 27·6 │ 4·4 │ ── │ 8·5 │ Do. │ │_Van Houten’s Cocoa_ │ 29·8 │ 4·4 │ ── │ 8·6 │ Do. │ │_Epps’s Prepared Cocoa_ │ 25·9 │ 1·5 │ 26 │ 3·1 │ Much │ │ │ │ │ │ │arrowroot.│ └───────────────────────────┴──────┴──────┴──────┴──────┴──────────┘
Some of the preparations of cocoa (_e.g._ Van Houten’s) have added to them alkaline salts to increase their solubility. Cocoa is not such a valuable food as might appear from the large amount of fat in it, because only moderate quantities of this can be taken without deranging digestion. In Vi-Cocoa a certain amount of kola is added, which contains a considerable proportion of caffeine. The addition of such a drug to a beverage is distinctly to be deprecated.
=Minor Stimulants.=—Beverages containing theine, or some analogous principle, appear to be employed in most countries. In moderate doses, they may assist the assimilation of other foods, but their main influence is on the nervous system. Theine-containing substances may be described as both sedative and exciting. They are sedative, in that they allay nervous irritability, and tend to “take the edge off” the disturbance caused by outward circumstances; and they are exciting, inasmuch as they are known to form an admirable antidote to the stupefying effects of opium or alcohol. The wakefulness from tea is an instance of the same thing, while the allaying of sensations of cold and hunger by a cup of tea is an instance of the sedative effect.
In Brazil, =Guarana= (from _Paullinia sorbilis_) is used as a drink; it contains theine, the quantity of which is twice as much as in good black tea, and five times as much as in coffee. Like green tea, a cup of guarana infusion is sometimes extremely valuable in nervous headaches.
In Peru, the natives use the leaves of the =Coca= plant (_Erythroxylon coca_), which must be carefully distinguished from cocoa. It is chewed somewhat in the same way as the betel-nut. It contains two alkaloids—cocaine and hygrine, as well as tannin. In its stimulant action it resembles tea and coffee. The active principle of this plant, =Cocaine=, is a valuable local anæsthetic. Internally it has been taken as a stimulant and restorative. Various wines containing Coca, with vaunted restorative powers, are advertised. They are mischievous when taken frequently. Nature’s remedy for fatigue, whether mental or body, is rest and recreation. Stimulants of this class, even though they enable work to be continued for awhile, eventually increase the exhaustion for which they are taken.
The =Kola-nut= is used in some parts of Western Africa as a stimulant. It is about the size of a pigeon’s egg, and has a bitter taste. The natives of Guinea generally take a piece of the seeds before each meal, and sometimes nibble it throughout the day.
=Kava= is prepared from the root of a kind of pepper. The natives of the Fiji islands commonly indulge in it. Its effects resemble those of coffee. In large doses, it destroys the power of walking, and may possibly produce impairment of vision.
The leaves of the _Ilex Paraguayense_, _Ilex Gongorrha_, and _Ilex Theezans_ are made into the beverage commonly known as =Paraguay tea= or maté.
The leaves of the =Hydrangea Thunbergii= are made into a beverage, which is designated in Japan “the tea of heaven.”
Among certain nations of Asia, the =Betel-nut= (from a palm called _Areca Catechu_) is chewed, after mixing small fragments with pepper and quicklime, and rolling in a palm leaf. The saliva is tinged blood-red, and a narcotic effect is said to be produced.
The dried flowering tops of the =Indian Hemp= (_Cannabis Indica_) are smoked by the Malays and others, or made into a beverage, called haschisch, which produces a kind of intoxication, in which murder has often been committed (hence, _assassins_ equals haschascheens).
The Kamtschatkans drink an infusion made from a fungus, known as the =Fly Agaric= (_Amanita Muscaria_), thus producing an intoxication similar to that from haschisch.
=Opium= in small doses is a stimulant, in large doses narcotic. The crude drug is sometimes taken, and less frequently the active principle, Morphia. It is frequently smoked, as well as taken internally. It is to be feared that secret opium taking is considerably increasing. The taking of morphia, especially hypodermically, is too common. Generally it has been first prescribed for neuralgia or some other complaint causing acute pain; and the patient, having experienced relief by its means, is tempted to revert to the practice apart from medical advice. Such a line of action is most pernicious. Eventually both the physical and the moral nature of the victim are shattered by it; and to break off this insidious habit, when once thoroughly established, is most difficult.
=Tobacco= may be conveniently mentioned here, though its usual effects are certainly not stimulant. It is smoked, chewed, or taken as snuff; when indulged in to excess it produces serious depression of the heart’s action, with frequent intermittence. In moderate doses it is sedative as well as slightly laxative. Prolonged indulgence in tobacco has produced many cases of incomplete blindness (_tobacco amblyopia_), in some cases it comes on with much smaller doses, and in all cases is only curable by ceasing to smoke. There is no sufficient ground for the statement that cigarette smoking is more injurious than smoking tobacco in a pipe or cigar, unless in the former case the smoke is inhaled into the lungs. The practice of smoking is injurious to growing boys, and should be strictly forbidden.
=Other Drugs= are now not infrequently taken, apart from medical advice. Of these the most commonly used are =Antipyrin= and =Phenacetin=, for headaches. Their use is injurious, and should not be entertained as a frequent practice. Sleeplessness frequently leads to the practice of taking chloral or sulphonal, or occasionally the inhalation of chloroform to induce sleep. (See also page 259). Remedies to induce sleep should never be taken except under immediate medical advice. They are only justifiable in extreme conditions, and if frequently taken tend to aggravate the conditions for which they are given.