Public School Domestic Science Part 7
Cuc.u.mbers are neither wholesome nor digestible.
ASPARAGUS.
Asparagus is a much prized vegetable. The substance called asparagin which it contains is supposed to possess some value.
RHUBARB.
Rhubarb is a wholesome vegetable.
ONIONS, GARLIC, SHALLOTS.
Onions, garlic, and shallots are valuable both as condiments and eaten separately. They contain more nutrients than the last vegetables considered.
CHAPTER VIII.
Fruits.
Fruits are composed largely of water, with starches, a vegetable jelly, pectin, cellulose and organic acids. The most important acids in fruit are citric, malic and tartaric. Citric acid is found in lemons, limes and oranges; tartaric acid in grapes; malic acid in apples, pears, peaches, apricots, gooseberries and currants. Among the least acid are peaches, sweet apples, bananas and prunes. Strawberries are moderately acid, while lemons and currants contain the most acid of all.
Uses of Fruit.
(1) To furnish nutriment; (2) to convey water to the system and relieve thirst; (3) to introduce various mineral matter (salts) and acids which improve the quality of the blood; (4) as anti-s...o...b..tics; (5) as laxatives and cathartics; (6) to stimulate the appet.i.te, improve digestion and provide variety in the diet. Apples, lemons and oranges are especially valuable for the potash salts, lime and magnesia they contain. Fruit as a common article of daily diet is highly beneficial, and should be used freely in season. Cooked fruit is more easily digested than raw, and when over-ripe should always be cooked in order to prevent fruit poisoning.
NUTS.
Nuts contain proteid, with some starch and sugar, but are not considered valuable as nutrients. Cocoanuts, almonds and English walnuts are the most nutritious.
Beverages.
TEA.
Tannin is an astringent of vegetable origin which exists in tea, is also found in coffee and wines, and is very injurious. Tea is a preparation made from the leaves of a shrub called Thea. The difference between black and green tea is due to the mode of preparation, and not to separate species of plant. Green tea contains more tannin than black. The following table will show the difference:--
=======================+===================+=================== | GREEN TEA. | BLACK TEA.
-----------------------+-------------------+------------------- Crude protein | 37.43 | 38.90 Fibre | 10.06 | 10.07 Ash (mineral matter) | 4.92 | 4.93 Theine | 3.20 | 3.30 Tannin | 10.64 | 4.89 Total nitrogen | 5.99 | 6.22 -----------------------+-------------------+-------------------
The stimulating properties which tea possesses, as well as its color and flavor, depend upon the season of the year at which the leaves are gathered, the variety of the plant, the age of the leaves, which become tough as they grow older, and the care exercised in their preparation. Much depends upon the manner in which tea is infused. (1) Use freshly boiled water; (2) allow it to infuse only three or four minutes, in order to avoid extracting the tannin. When carefully prepared as above, tea is not considered unwholesome for people in good health.
COFFEE.
Coffee is made from the berries of coffee-arabica, which are dried, roasted and browned. The following table gives an approximate idea of the composition of coffee beans (Konig):--
Water 1.15 Fat 14.48 Crude fibre 19.89 Ash (mineral matter) 4.75 Caffeine 1.24 Alb.u.minoids 13.98 Other nitrogenous matter 45.09 Sugar, gum and dextrin 1.66
Coffee is frequently adulterated with chicory, which is harmless.
Coffee should not be allowed to boil long or stand in the coffee pot over a fire, as the tannin is extracted, which renders it more indigestible. Much controversy has been indulged in over the effect of coffee upon the system, but like many other similar questions it has not reached a practical solution. The general opinion seems to be that when properly made and used in moderation it is a valuable stimulant and not harmful to adults.
COCOA.
Cocoa and chocolate contain more food substances than tea or coffee, although their use in this respect is not of much value. The following table gives the a.n.a.lysis of cocoa (Stutzer):--
Theobromine 1.73 Total nitrogenous substance 19.28 Fat 30.51 Water 3.83 Ash (mineral matter) 8.30 Fibre and non-nitrogenous extract 37.48
ALCOHOL.
The use of alcohol is wholly unnecessary for the health of the human organism. (See Public School Physiology and Temperance.)
Condiments.
Condiments and spices are used as food adjuncts; they supply little nourishment, the effect being mainly stimulating, and are very injurious when used in excess. They add flavor to food and relieve monotony of diet. The use of such condiments as pepper, curry, pickles, vinegar and mustard, if abused, is decidedly harmful. Salt is the only necessary condiment, for reasons given in the chapter on mineral matter. The blending of flavors so as to make food more palatable without being injured is one of the fine arts in cookery.
Some flavors, such as lemon juice, vinegar, etc., increase the solvent properties of the gastric juice, making certain foods more digestible.
CHAPTER IX.
Preparing Food.
The knowledge of food values and their relation to the body will be of little use for practical purposes unless combined with the knowledge of how the various foods should be prepared, either by cooking or in whatever form circ.u.mstances and the material may require. The first requisite for cooking purposes is heat; this necessitates the use of fuel. The fuels chiefly used for household purposes are wood, coal, kerosene oil and gas. Soft woods, such as pine or birch, are best for kindling and for a quick fire. Hard woods, oak, ash, etc., burn more slowly, retain the heat longer, and are better adapted for cooking purposes.
COAL.
Coal (anthracite) is about 95 per cent. carbon. It kindles slowly, gives a steady heat, and burns for a longer time without attention than wood. Stoves for burning oil and gas have become popular, and are very convenient and satisfactory for cooking purposes.
OIL.
Oil is considered to be the cheapest fuel.
GAS.
Gas is a very satisfactory fuel for cooking purposes, but can only be used in certain localities.
Making and Care of a Fire.
CARE OF A FIRE.
Great care should be exercised in the selection of a stove or range.
The plainer the range the easier it will be to keep it clean. There should be plenty of dampers that can be used to hasten the fire or to check it. Learn thoroughly the management of the range before beginning to cook. In lighting a fire, remove the covers, brush the soot from the top of the oven into the fire-box; clean out the grate (saving all the unburned coal, and cinders). Put in shavings or paper, then kindling arranged crosswise, allowing plenty of air s.p.a.ce between the pieces, a little hard wood and a single layer of coal. Put on the covers, open the direct draft and oven damper, then light the paper.