Sunday, May 17, 2009

The Chemistry of Vegetable Food

We come now to the vegetable kingdom, the principal points that we are to consider arranging themselves somewhat as follows:—

Farinaceous seeds,
Oleaginous seeds,
Leguminous seeds,
Tubers and roots,
Herbaceous articles,
Saccharine and farinaceous preparations.

Under the first head, that of farinaceous seeds, are included wheat, rye, oats, Indian corn, rice, and a variety of less-known grains, all possessing in greater or less degree the same constituents. It will be impossible to more than touch upon many of them; and wheat must stand as the representative, being the best-known and most widely used of all grains. Each one is made up of nitrogenous compounds, gluten, albumen, caseine, and fibrine, gluten being the most valuable. Starch, dextrine, sugar, and cellulose are also found; fatty matter, which gives the characteristic odor of grain; mineral substances, as phosphates of lime and magnesia, salts of potash and soda, and silica, which we shall shortly mention again.

Hard Wheat, or that grown in hot climates and on fertile soil, has much more nitrogen than that of colder countries. In hard wheat, in a hundred parts, twenty-two will be of nitrogen, fifty-nine starch, ten dextrine, &c, four cellulose, two and a half of fatty matter, and three of mineral, thus giving many of the constituents found in animal food.

This wheat is taken as bread, white or brown, biscuits, crackers, various preparations of the grain whether whole or crushed, and among the Italians as macaroni, the most condensed form of cereal food. The best macaroni is made from the red wheat grown along the Mediterranean Sea, a hot summer and warm climate producing a grain, rich, as already mentioned, in nitrogen, and with a smaller proportion of water than farther north. The intense though short summer of our own far North-west seems to bring somewhat the same result, but the outer husk is harder. This husk was for years considered a necessity in all really nutritious bread; and a generation of vegetarians taking their name from Dr. Graham, and known as Grahamites, conceived the idea of living upon the wheaten flour in which husk and kernel were ground together. Now, to stomachs and livers brought to great grief by persistent pie and doughnuts and some other New-England wickednesses, these husks did a certain office of stimulation, stirring up jaded digestions, and really seeming to arrest or modify long-standing dyspepsia. But they did not know what we do, that this outer husk is a layer of pure silica, one of the hardest of known minerals. Boil it six weeks, and it comes out unchanged. Boil it six years, or six centuries, and the result would be the same. You can not stew a grindstone or bring granite to porridge, and the wheat-husk is equally obstinate. So long as enthusiasts ate husk and kernel ground together, little harm was done. But when a more progressive soul declared that in bran alone the true nutriment lay, and a host of would-be healthier people proceeded to eat bran and preach bran, there came a time when eating and preaching both stopped, from sheer want of strength to go on. The enthusiasts were literally starving themselves to death—for starvation is by no means mere deprivation of food: on the contrary, a man may eat heartily to the day of his death, and feel no inconvenience, so far as any protest of the stomach is concerned, yet the verdict of the wise physician would be, "Died of starvation." If the food was unsuitable, and could not be assimilated, this was inevitable. Blood, muscle, nerve—each must have its fitting food; and thus it is easy to see why knowledge is the first condition of healthful living. The moral is: Never rashly experiment in diet till sure what you are about, and, if you can not for yourselves find out the nature of your projected food, call upon some one who can.

Where wheat is ground whole, it includes six and a half parts of heat-producers to one of flesh-formers. The amount of starch varies greatly. Two processes of making flour are now in use,—one the old, or St. Louis process; the other, the "new process," giving Haxall flour. In the former, grindstones were used, which often reached so great a degree of heat as to injure the flour; and repeated siftings gave the various grades. In the new, the outer husk is rejected, and a system of knives is used, which chop the grain to powder, and it is claimed do not heat it. The product is more starchy, and for this reason less desirable. We eat far too much heat-producing food, and any thing which gives us the gluten of the grain is more wholesome, and thus "seconds" is really a more nutritious flour than the finer grades. Try for yourselves a small experiment, and you will learn the nature of flour better than in pages of description.

Take a little flour; wet it with cold water enough to form a dough. Place it on a sieve, and, while working it with one hand, pour a steady stream of water over it with another. Shortly you will find a grayish, tough, elastic lump before you, while in the pan below, when the water is carefully poured off, will be pure wheat-starch, the water itself containing all the sugar, dextrine or gum, and mineral matter. This toughness and elasticity of gluten is an important quality; for in bread-making, were it not for the gluten, the carbonic-acid gas formed by the action of yeast on dough would all escape. But, though it works its way out vigorously enough to swell up each cell, the gluten binds it fast, and enables us to have a panful of light "sponge," where a few hours before was only a third of a pan.

Starch, as you have seen, will not dissolve in the cold water. Dry it, after the water is poured on, and minute grains remain. Look at these grains under a microscope, and each one is cased in a thick skin, which cold water can not dissolve. In boiling water, the skins crack, and the inside swells and becomes gummy. Long boiling is thus an essential for all starchy foods.

Bread proper is simply flour, water, and salt, mixed to a firm dough and baked. Such bread as this, Abram gave to his angelic guests, and at this day the Bedouin Arab bakes it on his heated stone. But bread, as we understand it, is always lightened by the addition of yeast or some form of baking-powder, yeast making the most wholesome as well as most palatable bread. Carbonic-acid gas is the active agent required; and yeast so acts upon the little starch-granules, which the microscope shows as forming the finest flour, that this gas is formed and evenly distributed through the whole dough. The process is slow, and in the action some of the natural sweetness of the flour is lost. In what is known as aërated bread, the gas made was forced directly into the dough, by means of a machine invented for the purpose; and a very scientific and very good bread it is. But it demands an apparatus not to be had save at great expense, and the older fashions give a sufficiently sweet and desirable bread.

Rye and Indian Corn form the next best-known varieties of flour in bread-making; but barley and oats are also used, and beans, pease, rice, chestnuts, in short, any farinaceous seed, or legume rich in starch, can fill the office.

Oatmeal may take rank as one of the best and most digestible forms of farinaceous food. Some twenty-eight per cent of the grain is husk, seventy-two being kernel; and this kernel forms a meal containing twelve parts of nitrogenous matter, sixty-three of carbo-hydrates, five and a half of fatty matter, three of saline, and fifteen of water. So little gluten is found, that the flour of oats can not be made into loaves of bread; although, mixed and baked as thin cakes, it forms a large part of the Scotchman's food. It requires thorough cooking, and is then slightly laxative and very easily digested.

Buckwheat is very rich in nitrogenous substances, and as we eat it, in the form of cakes with butter and sirup, so heating a food, as to be only suitable for hard workers in cold weather.

Indian corn has also a very small proportion of gluten, and thus makes a bread which crumbles too readily. But it is the favorite form of bread, not only for South and West in our own country, but in Spanish America, Southern Europe, Germany, and Ireland. It contains a larger amount of fatty matter than any other grain, this making it a necessity in fattening animals. In a hundred parts are eleven of nitrogen, sixty-five of carbo-hydrates, eight of fatty matter, one and a half of saline, and fourteen of water. The large amount of fatty matter makes it difficult to keep much meal on hand, as it grows rancid and breeds worms; and it is best that it should be ground in small quantities as required.

Rice abounds in starch. In a hundred parts are found seven and a half of nitrogen, eighty-eight of starch, one of dextrine, eight-tenths of fatty matter, one of cellulose, and nine-tenths of mineral matter. Taken alone it can not be called a nutritive food; but eaten with butter or milk and eggs, or as by the East Indians in curry, it holds an important place.

We come now to OLEAGINOUS SEEDS; nuts, the cocoanut, almonds, &c, coming under this head. While they are rich in oil, this very fact makes them indigestible, and they should be eaten sparingly.

Olive-oil must find mention here. No fat of either the animal or vegetable kingdom surpasses this in delicacy and purity. Palm-oil fills its place with the Asiatics in part; but the olive has no peer in this respect, and we lose greatly in our general distaste for this form of food. The liking for it should be encouraged as decidedly as the liking for butter. It is less heating, more soothing to the tissues, and from childhood to old age its liberal use prevents many forms of disease, as well as equalizes digestion in general.

LEGUMINOUS SEEDS are of more importance, embracing as they do the whole tribe of beans, pease, and lentils. Twice as much nitrogen is found in beans as in wheat; and they rank so near to animal food, that by the addition of a little fat they practically can take its place. Bacon and beans have thus been associated for centuries, and New England owes to Assyria the model for the present Boston bean-pot. In the best table-bean, either Lima or the butter-bean, will be found in a hundred parts, thirty of nitrogen, fifty-six of starch, one and a half of cellulose, two of fatty matter, three and a half of saline, and eight and a half of water. The proportion of nitrogen is less in pease, but about the same in lentils. The chestnut also comes under this head, and is largely eaten in Spain and Italy, either boiled, or dried and ground into flour.

TUBERS and ROOTS follow, and of these the Potato leads the van. Low as you may have noticed their standing on the food-table to be, they are the most economical and valuable of foods, combining as well with others, and as little cloying to the palate, as bread itself. Each pound of potatoes contains seven hundred and seventy grains of carbon, and twenty-four grains of nitrogen; each pound of wheat-flour, two thousand grains of carbon, and one hundred and twenty of nitrogen. But the average cost of the pound of potatoes is but one cent; that of the pound of wheat, four. It is obtainable at all seasons, and thus invaluable as a permanent store, though best in the winter. Spring, the germinating season, diminishes its nutritive value. New potatoes are less nutritious than older ones, and in cooking, if slightly underdone, are said to satisfy the appetite better; this being the reason why the laboring classes prefer them, as they say, "with a bone in them."

In a hundred parts are found but two of nitrogen, eighteen of starch, three of sugar, two-tenths of fat, seven-tenths of saline matter, and seventy-five parts of water. The Sweet-potato, Yam, and Artichoke are all of the same character. Other Tubers, the Turnip, Beet, Carrot, and Parsnip, are in ordinary use. The turnip is nine-tenths water, but possesses some valuable qualities. The beet, though also largely water, has also a good deal of sugar, and is excellent food. Carrots and parsnips are much alike in composition. Carrots are generally rejected as food, but properly cooked are very appetizing, their greatest use, however, being in soups and stews.

HERBACEOUS ARTICLES follow; and, though we are not accustomed to consider Cabbage as an herb, it began existence as cole-wort, a shrub or herb on the south coast of England. Cultivation has developed it into a firm round head; and as a vegetable, abounding as it does in nitrogen, it ranks next to beans as a food. Cauliflower is a very delicate and highly prized form of cabbage, but cabbage itself can be so cooked as to strongly resemble it.

Onions are next in value, being much milder and sweeter when grown in a warm climate, but used chiefly as a flavoring. Lettuce and Celery are especially valuable; the former for salads, the latter to be eaten without dressing though it is excellent cooked. Tomatoes are really a fruit, though eaten as a vegetable, and are of especial value as a cooling food. Egg-plant, cucumbers, &c., all demand space; and so with edible fungi, mushrooms, and truffles, the latter the property of the epicure, and really not so desirable as that fact would indicate.

FRUITS are last in order; and among these stands first of all the apple. While in actual analysis fruits have less nutritive value than vegetables, their acids and salts give to them the power of counteracting the unhealthy states brought about by the long use of dried or salted provisions. They are a corrective also of the many evils arising from profuse meat-eating, the citric acid of lemons and grape-fruit being an antidote to rheumatic and gouty difficulties. Cold storage now enables one to command grapes long after their actual season has ended, and they are invaluable food. The brain-worker is learning to depend more and more on fruit in all its forms; and apples lead the list, containing more solid nutriment than any other form. While considered less digestible raw than baked, they are still one of the most attractive, life-giving forms of food, and if eaten daily would prove a standard antidote to patent medicine. The list of fruits is too long for mention here; but all have their specific uses, and are necessary to perfect health.

SUGAR and HONEY follow in the stores of the vegetable kingdom. Cane-sugar and glucose, or grape-sugar, are the two recognized varieties, though the making of beet-sugar has become an industry here as well as in France. Grape-sugar requires to be used in five times the amount of cane, to secure the same degree of sweetness. Honey also is a food,—a concentrated solution of sugar, mixed with odorous, gummy, and waxy matters. It possesses much the same food value as sugar, and is easily digested.

With the various FARINACEOUS PREPARATIONS, Sago, Tapioca, Arrow-root, &c, the vegetable dietary ends. All are light, digestible foods, principally starchy in character, but with little nutriment unless united with milk or eggs. Their chief use is in the sick-room.

Restricted as comment must be, each topic introduced will well reward study; and the story of each of these varied ingredients in cookery, if well learned, will give one an unsuspected range of thought, and a new sense of the wealth that may be hidden in very common things.

Taken from:

Adapted to Domestic Use or Study in Classes

Copyright 1903
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