Chapter 3

Pulse, or Legumes, includes haricots and other beans, peas and lentils. The proteid contained is that variety known as legumin, which is either the same, or is closely allied, to the casein of milk and cheese. Pulse is very rich in proteid, the dried kinds in general use, contain 24 or 25 per cent. The richest is the soy-bean, which is used in China and Japan, it contains 35 per cent., besides 19 per cent. of fat. Pulse requires thorough cooking, haricots taking the longest time. Split lentils are cooked sooner, and are better digested; this is chiefly due to the removal of the skins. The haricots, bought from small grocers who have a slow sale, are often old, and will not cook tender. Pulse is best adapted to the labouring classes; the sedentary should eat it sparingly, it is liable to cause flatulence or accumulation of gas in the intestines, and constipation. Haricots are easier to digest when mashed and mixed with other food. Pulse was formerly stated to leave much undigested residue. Recent experiments have shown that it is satisfactorily digested under favourable conditions. Strümpell found beans in their skins to leave a large proportion of proteid matter unabsorbed. Lentil meal mixed with other food was digested in a perfectly satisfactory manner. Another experimenter (Rubner) found that when even the very large quantity of 1-1/8 pound of dried split peas per day were eaten, only 17 per cent. of proteid matter was unabsorbed, which compares very well with the 11 per cent. of proteid left from a macaroni diet, with which the same man was fed at another time. Had a reasonable quantity of peas been eaten per day, the quantity undigested would probably have differed little from that of other foods.

Nuts are, as a rule, very rich in oil and contain a fair proportion of proteid; when well masticated they are a very valuable food. Walnuts are one of the best, and the kernels can be purchased shelled, thus avoiding much trouble. They can be finely ground in a nut-mill and used for several purposes, mixed in the proportion of about two ounces to the pound of wheatmeal they produce a rich flavoured bread. They can also he used in sweet cakes and in rich puddings to increase their food value, lightness and taste. Pine kernels being very oily, can be used with flour in the place of lard or butter.

Fruits are generally looked upon as luxuries, rather than as food capable of supplying a meal or a substantial part of one. They are usually eaten only when the appetite has been appeased by what is considered more substantial fare. Fresh fruits contain a larger proportion of water than nearly all other raw foods, and consequently the proportion of nourishment is small; but we must not despise them on this account. Milk contains as much or more water. Certain foods which in the raw state contain very little water, such as the pulses and cereals when cooked absorb a very large quantity; this is particularly the case in making porridge. Cabbage, cauliflower, Spanish onions and turnips, after cooking contain even 97 per cent. of water. Roast beef contains on an average 48 per cent., and cooked round steak with fat removed 63 per cent. of water. It is customary at meal times to drink water, tea, coffee, beer, wine, &c. When a meal contains any considerable quantity of fresh fruits there need be no desire to drink. Notwithstanding that fruits contain so much water, a dietary consisting of fruits with nuts, to which may be added bread and vegetables, will contain less water than the total quantity usually consumed by a person taking the more customary highly cooked and seasoned foods. An advantage is that the water in fruits is in a wholesome condition, free from the pollution often met with in the water used for drinking purposes. Raw fruits favour mastication, with its consequent advantages, whilst cooked and soft food discourages it. Plums and what are termed stone fruits, if eaten in more than very small quantities, are apt to disagree. Persons with good digestions can take fruit with bread, biscuits and with uncooked foods without any inconvenience. Fruit is more likely to disagree when taken in conjunction with elaborately cooked foods. Many cannot take fruit, especially if it be acid, at the same time as cereal or starchy substances, and the difficulty is said to be greater at the morning's meal. If the indigestion produced is due to the acid of the fruit preventing the saliva acting on the starch, scientific principles would direct that the fruit be eaten quite towards the end of the meal. The same consideration condemns the use of mint sauce, cucumber and vinegar, or pickles, with potatoes and bread, or even mint sauce with green peas. Bananas are an exception, as not interfering with the digestion of starch. Bananas are generally eaten in an unripe condition, white and somewhat mealy; they should be kept until the starch has been converted into sugar, when they are both more pleasant and wholesome. Nuts and fruit go well together. For a portable meal, stoned raisins or other dried fruit and walnut kernels or other nuts are excellent.

What has been called a defect in most fruits, is the fact that the proteid is small in proportion to the other constituents. This has been too much dwelt upon, owing to the prevailing exaggerated idea of the quantity of proteid required. The tomato contains a large proportion, though the water is very high. Bananas, grapes and strawberries contain to each part of proteid from 10 to 12 parts of other solid nutritive constituents (any oil being calculated into starch equivalents); this is termed the nutritive ratio. Although this may seem a small proportion of proteid, there are reasons for believing that it is sufficient. Taking the average of 29 analyses of American apples, a nutritive ratio of 33 was obtained. If it were suggested that life should be sustained on apples alone, this small quantity of proteid would be an insurmountable difficulty. As the addition of nuts or other nutritious food sufficiently increases the proteid, no objection can with justice be made against the use of fruit. A study of our teeth, digestive organs and general structure, and of comparative anatomy, points to fruits, nuts and succulent vegetables as our original diet.

The potash and other salts of the organic acids in fruits tend to keep the blood properly alkaline. Where there is a tendency to the deposition of uric acid in the body, they hinder its formation. Citric, tartaric, malic and other organic acids exist in fruits in combination with potash and other bases, as well as in the free state. The free acids in fruits, when eaten, combine with the alkalies in the intestinal tract, and are absorbed by the body and pass into the blood, not as acids, but as neutral salts. Here they are converted into potassium carbonate or some other carbonate. Fruit acids never make the blood acid but the reverse. Fruit salts and acids are antiscorbutic. Fruits have often proved of the greatest benefit in illness. What is known as the grape cure has been productive of much good. Lemons and oranges have also been of great benefit. Strawberries have been craved for and have proved of the greatest advantage in some extreme cases of illness when more concentrated food could not be endured. Fruit is coming into greater use, especially owing to its better distribution and lessened cost. Fruit is not as cheap as it should be, as it can be produced in great abundance at little cost, and with comparatively little labour. The price paid by the public greatly exceeds the real cost of production. A very large proportion, often the greater part of the cost to the consumer, goes in railway and other rates and in middle-men's profits. It is commonly cheaper to bring fruit from over the sea, including land carriage on either side, than it is to transport English produce from one part of our country to another. English homegrown fruit would be cheaper were it not for the difficulty of buying suitable land at a reasonable price, and the cost of transit. For the production of prime fruit there is a lack of sufficient intelligence, of scientific culture and co-operation.

Vegetables--using the name in its popular sense--contain valuable saline constituents or salts. By the usual method of cooking a large proportion of the salts is lost. It is better to steam than to boil them. The fibrous portion of vegetables is not all digested, but it is useful in stimulating the peristaltic action of the bowels and lessening any tendency to constipation. Vegetables are more especially useful to non-vegetarians to correct the defects of their other food.

The potato belongs to a poisonous order--the _Solanacæ_. There is a little alkaloid in the skin, but this is lost in the cooking. The eyes and sprouting portions contain the most and should be cut out.

Fungi.--There are about a hundred edible species in this country, but many of the fungi are poisonous, some intensely so. It can scarcely be expected that these lowly organised plants, differing so much in their manner of growth from the green or chlorophyll bearing plants, can be particularly nourishing. It is only the fructifying part, which appears above the ground, that is generally eaten. It is of very rapid growth. Of 9 edible fungi of 4 species, obtained in the Belgrade market, the average amount of water was 89.3 per cent., leaving only 10.7 per cent. of solid matter; the average of fat was 0.55 per cent. The food value of fungi has been greatly over-rated. In most of the analyses given in text-books and elsewhere, the total nitrogen has been multiplied by 6.25 and the result expressed as proteid. The amount of nitrogen in a form useless for the purpose of nutrition is about a third of the whole. Of the remainder or proteid nitrogen, it is said much is not assimilated, sometimes quite half, owing to the somewhat indigestible character of the fungi. An analysis of the common mushroom gave proteids 2.2 per cent., amides (useless nitrogenous compounds) 1.3 per cent., and water 93.7 per cent. The fungi are of inferior nutritive value to many fresh vegetables and are much more expensive. Their chief value is as a flavouring.

Milk and Eggs are permissible in a vegetarian dietary, and as a rule, vegetarians use them. Eggs, with the exception of such as are unfertile, are of course alive; but they have no conscious existence, and cannot be said to suffer any pain on being killed and eaten. An objection to their use as food is, that on an egg and poultry farm, the superfluous male birds are killed, and as the hens become unprofitable layers they are also killed. A similar humane objection applies to the use of cow's milk by man. The calves are deprived of part of their natural food, the deficiency being perhaps made up by unnatural farinaceous milk substitutes. Many of the calves, especially the bull calves, are killed, thus leaving all the milk for human use. When cows cease to yield sufficient milk they too are slaughtered. Milch cows are commonly kept in unhealthy houses, deprived of exercise and pure air, crowded together, with filthy evil smelling floors reeking with their excrements, tended by uncleanly people. With no exercise and a rich stimulating diet they produce more milk; but it is no matter for surprise that tuberculosis is common amongst them. When the lesions of tubercle (consumption) are localised and not excessive, the rest of the carcase is passed by veterinary surgeons as fit for food; were it otherwise, enormous quantities of meat would be destroyed. As butcher's meat is seldom officially inspected, but a very small part is judged by the butchers as too bad for food. In mitigation it may be said that poultry lead a happy existence and their death is, or should be, quickly produced with but little pain, probably less pain than if left to die from natural causes. The same cannot be said of cattle and sheep when the time arrives for their transport to the slaughter man's. It is argued by vegetarians who take milk and animal products that they are not responsible for the death of the animals, as they do not eat their flesh. As vegetarians profit by conditions in which the slaughtering of the animals is a part, they cannot be altogether exonerated. Cow's milk is prone to absorb bad odours, and it forms a most suitable breeding or nutrient medium for most species of bacteria which may accidentally get therein. By means of milk many epidemics have been spread, of scarlet fever, diphtheria, cholera, and typhoid. Occasionally milk contains tubercle bacilli from the cows themselves. By boiling, all bacteria, except a few which may be left out of consideration, are destroyed. Such a temperature, however, renders the milk less digestible and wholesome for infants. By heating to 160° F. or 170° F. for a few minutes, such pathogenic germs as are at all likely to be in milk (tubercle, typhoid, diphtheria, &c.) are killed, and the value of the milk is but little affected: this is called Pasteurising. It was until quite recently a common practice to add boric acid, formaldehyde and other preservatives; this has injured the vitality and caused the death of many infants. They have not yet gone quite out of use.

For infants the only satisfactory food is that of a healthy mother. On account of physical defects in the mother, or often for merely selfish reasons, the infant is deprived of its natural food. Many attempts have been made to bring cow's milk to approximately the same composition as human milk. It can be done by adding water, milk sugar and cream of known composition, in certain proportions. Great difficulties are met with when this is put into practice. The simplest method is that of Professor Soxhlet. The proper quantity of milk sugar is added, but instead of adding the right quantity of cream or fat--a very difficult thing to do--the equivalent quantity of extra milk sugar is used. Although not theoretically satisfactory, in practice it answers very well. We have found it to agree very well with infants. To cow's milk of pure average quality, add half its volume of water containing 12.3 per cent. of milk sugar; or, what amounts to the same thing, to a pint of cow's milk add one and a quarter ounce of milk sugar and half-a-pint of water. It is preferable to Pasteurise by placing the bottle of milk in a vessel of water. This water is to be heated until the milk shows a temperature of about 75° C. or 165° F., but must not exceed 80° C. or a change in the albumen of the milk takes place which affects its digestibility. Keep at this temperature for about ten minutes. If not required at once, a plug of cotton wool should be placed in the neck of the bottle, and it should be kept in a cold place until required. Professor Soxhlet does not advise the addition of lime water. The proteids are not of the same composition as in human milk (the calf being a ruminating animal)--and it is a common plan to add water or barley water to milk until it is so watered down that it cannot curdle into tough curds. An infant has thus either to distend its stomach with a large quantity of watery nourishment, or else to get insufficient food. Sometimes it is necessary to peptonise the milk a little. At the Leipzig infants hospital, and also the Hygienic Institute, they give to infants, up to 9 months old, Prof. Soxhlet's mixture, except that an equal volume of water is added to the milk. Milk, cheese, and especially hen's eggs contain a very large proportion of proteid. When added to food poor in proteid they improve its nutritive quality. It has often been said, and with truth, that some vegetarians by the profuse use of animal products, consume as much, or even more proteid of animal origin than the average person who includes flesh food in his dietary. An excess of proteid from these sources is less injurious as eggs contain no purins, and milk but a very small quantity. In support of the use of animal products, it may be said that we have become so fond of animal foods and stimulating drinks, that the use of milk, butter, cheese and eggs renders the transition to a dietary derived from the vegetable kingdom much easier. By means of these, cooked dishes can be produced which approach and sometimes can scarcely be distinguished from those of cooked flesh.

In the present state of society, when really good vegetarian fare is difficult to procure away from home, eggs, cheese, and milk are a great convenience.

Digestion.--The digestive juices contain certain unorganised ferments, which produce chemical changes in the food. If the food is solid, it has to be liquefied. Even if already liquid it has generally to undergo a chemical change before being fitted for absorption into the body. The alimentary canal is a tubular passage which is first expanded into the mouth, and later into the stomach. As the food passes down, it is acted upon by several digestive juices, and in the small intestine the nutritive matter is absorbed, whilst the residue passes away.

The saliva is the first digestive juice. It is alkaline and contains a ferment called ptyalin. This acts energetically on the cooked and gelatinous starch, and slowly on the raw starch. Starch is quite insoluble in water, but the first product of salivary digestion is a less complex substance called soluble-starch. When time is allowed for the action to be completed, the starch is converted into one of the sugars called maltose. In infants this property of acting on starch does not appear in effective degree until the sixth or seventh month, and starch should not be given before that time. Only a small quantity should be provided before the twelfth month, when it may be gradually increased. Dr. Sims Wallace has suggested that the eruption of the lower incisors from the seventh to the eighth month, was for the purpose of enabling the infant--in the pre-cooking stage of man's existence--to pierce the outer covering of fruits so as to permit his extracting the soluble contents by suction; and accordingly when these teeth are cut we may allow the child to bite at such vegetable substances as apples, oranges, and sugar cane. Dr. Harry Campbell says that starch should be given to the young, "not as is the custom, as liquid or pap, but in a form compelling vigorous mastication, for it is certain that early man, from the time he emerged from the ape till he discovered how to cook his vegetable food, obtained practically all his starch in such a form. If it is given as liquid or pap it will pass down as starch into the stomach, to setup disturbance in that organ; while if it is administered in a form which obliges the child to chew it properly, not only will the jaws, the teeth, and the gums obtain the exercise which they crave, and without which they cannot develop normally, but the starch will be thoroughly insalivated that much of it will be converted within the mouth into maltose. Hard well baked crusts constitute a convenient form in which to administer starch to children. A piece of crust may be put in the oven and rebaked, and spread with butter. Later, we may give hard plain biscuits." Dr. Campbell continues, that he does not say that starch in the pappy form, or as porridge, should find no place whatever in man's dietary at the present day, but we should arrange that a large proportion of our food is in a form inviting mastication.

The teeth perform the very important function of breaking down our food and enabling it to be intimately incorporated with the saliva and afterwards with the digestive juices. The Anglo-Saxon race shows a greater tendency to degeneracy in the teeth than do other races; the teeth of the present generation are less perfect than those of previous generations. A dentist writes (_Lancet_, 1903-2, p. 1054) "I have had the opportunity of examining the teeth of many natives in their more or less uncivilised state, from the Red Indians of North America, the negroes of Africa, to the more civilised Chinese, Japanese, and Indians of the East, and I have usually found them possessed of sound teeth, but so soon as they come under the influence of civilised life in Washington, Montreal, London, Paris and other cities, their teeth begin to degenerate, though their general health may remain good." In a long article on mastication in the _Lancet_ (1903-2, p. 84) from which we have already quoted, Dr. Harry Campbell gives as the effect of thorough and efficient mastication, that it increases the amount of alkaline saliva passing into the stomach, and prolongs the period of starch digestion within that organ. That it influences the stomach reflexly by promoting the flow of gastric juice. That the frequent use of the jaws and the tongue, during the period of growth, cause the jaws to expand. If the jaws are not adequately exercised during this period, owing to the use of soft food, they do not reach their normal size, the teeth are overcrowded, do not develop fully, and are prone to decay. The effect of vigorous mastication is to stimulate the circulation in the tooth pulp, which promotes nutrition and maintains a firm dental setting. Dr. Campbell writes: "I am perfectly at one with Dr. Wallace, in believing that the removal of the fibrous portion of food is the main cause of the prevalence of caries among moderns."

When the food reaches the stomach, gastric juice is secreted. This juice contains a ferment called pepsin and hydrochloric acid. Pepsin is only active in an acid media. Starch digestion proceeds in the stomach to such a time--stated as from 15 to 30 minutes--when the acid gastric juice has been poured out in sufficient quantity to neutralise the alkalinity of the saliva. The gastric juice acts upon the proteids only. After a time the liquefied contents of the stomach are passed into the first portion of the small intestine, called the duodenum. Here it meets with the pancreatic juice, which like the gastric juice attacks proteids, but even more energetically, and only in an alkaline media. The proteolitic ferment is called trypsin. The pancreatic, the most important of the digestive fluids, contains other ferments; one called amylopsin, takes up the digestion of any remaining or imperfectly converted starch left from the salivary digestion. Amylopsin is much more powerful and rapid than the ptyalin of the saliva, especially on uncooked starch. Its absence from the pancreatic juice of infants is an indication that starch should not be given them. Another ferment, stearopsin, emulsifies fats. The bile is alkaline and assists the pancreatic juice in neutralising the acid mixture that leaves the stomach; it also assists the absorption of fats. The digestion of proteids is not completed in the stomach. There are some who look upon the stomach as chiefly of use as a receptacle for the large mass of food, which is too quickly eaten to be passed at once into the intestines; the food being gradually expelled from the stomach, in such quantities as the duodenal digestion can adequately treat. A frequently used table, showing the time required for the digestion of various foods in the stomach, is of little practical value. There is ample provision for the digestion of food, there is a duplication of ferments for the proteids and starch. In health, the ferments are not only very active, but are secreted in ample quantities. The digestive or unorganised ferments must not be confused with the organised ferments such as yeast. The latter are living vegetable cells, capable of indefinite multiplication. The former are soluble bodies, and though capable of transforming or digesting some thousands of times their mass of food, their power in this direction is restricted within definite limits. Another and preferable name for them is enzymes.