MRS. J. HOODLESS,
President School Of Domestic Science, Hamilton.
This Book may be used as a Text-Book in any High or Public School, if so ordered by a resolution of the Trustees.
TORONTO: THE COPP, CLARK COMPANY, LIMITED, 1898.
Entered according to Act of the Parliament of Canada, in the year one thousand eight hundred and ninety-eight, by THE COPP, CLARK COMPANY, LIMITED, Toronto, Ontario, in the Office of the Minister of Agriculture.
"I have come to the conclusion that more than half the disease which embitters the latter half of life is due to avoidable errors in diet, and that more mischief in the form of actual disease, of impaired vigour, and of shortened life, accrues to civilized man in England and throughout Central Europe from erroneous habits of eating than from the habitual use of alcoholic drink, considerable as I know that evil to be."—Sir Henry Thompson.
* * * * *
"Knowledge which subserves self-preservation by preventing loss of health is of primary importance. We do not contend that possession of such knowledge would by any means wholly remedy the evil. But we do contend that the right knowledge impressed in the right way would effect much; and we further contend that as the laws of health must be recognized before they can be fully conformed to, the imparting of such knowledge must precede a more rational living."—Herbert Spencer.
* * * * *
"Cooking means the knowledge of Medea and Circe, and of Calypso and Helen, and of Rebekah, and of the Queen of Sheba. It means the knowledge of all fruits, and herbs, and balms, and spices, and of all that is healing and sweet in fields and groves, and savory in meats; it means carefulness, and inventiveness, and watchfulness, and willingness, and readiness of appliance; it means much tasting and no wasting; it means English thoroughness, and French art, and Arabian hospitality; it means, in fine, that you are to be perfect and always 'ladies'—'loaf-givers.'"—Ruskin.
An eminent authority says: "Up to the age of sixteen even a lucid statement of principles is received by all but a few pupils as dogma. They do not and cannot in any adequate sense realize the reasoning process by which scientific conclusions are reached. They are taught not only facts but classifications and laws, and causes in relation to their effect. These are not, in the majority of cases, elaborated by the pupil. The teaching of them accordingly degenerates into a statement of facts, and the learning of them into an act of memory."
To obviate this condition, or to at least neutralize its effects somewhat, is one of the principal reasons for introducing Domestic Science into the Public School curriculum; a science which relates so closely to the daily life that it cannot be left to an act of memory; where cause and effect are so palpable that the pupil may readily arrive at an individual conclusion.
The aim of this text-book is to assist the pupil in acquiring a knowledge of the fundamental principles of correct living, to co-ordinate the regular school studies so as to make a practical use of knowledge already acquired. Arithmetic plays an important part in the arranging of weights and measures, in the study of the analysis and relative value of various kinds of food, in estimating the cost of manufactured products in proportion to their market value, in the purchase of food material, etc. History and geography are closely allied to the study of the diet and customs of the different countries, with their variety of climate and products. Physiology and temperance principles permeate the whole course of study. In addition to these are the direct lessons, provided by the practice work, in neatness, promptness and cleanliness. It will therefore be necessary to have a wide general knowledge before entering upon a course in Domestic Science.
Owing to the limited time allowed for this course in the Public Schools, it will be impossible to teach more than a few of the first principles governing each department of the work, viz., a knowledge of the constituent parts of the human body; the classification of food and the relation of each class to the sustenance and repair of the body; simple recipes illustrating the most wholesome and economical methods of preparing the various kinds of food; the science of nutrition, economy and hygiene; general hints on household management, laundry work, and care of the sick.
To enter more fully into the chemistry of food, bacteriology, etc., would tend to cause confusion in the mind of the average school girl, and possibly create a distaste for knowledge containing so much abstract matter.
This book is not a teacher's manual, nor is it intended to take the place of the teacher in any way. The normal training prescribed for teachers will enable them to supplement the information contained herein, by a much more general and comprehensive treatment of the various questions, than would be possible or judicious in a primary text-book. It has been found difficult for pupils to copy the recipes given with each lesson, or to write out the instructions carefully without infringing upon the time which should be devoted to practice work. In order to meet this difficulty, also to enable the pupil to work at home under the same rules which govern the class work, simple recipes are given, beginning with a class requiring a knowledge of heat and its effect, going on to those requiring hand dexterity, before attempting the more difficult subjects. After the pupils have acquired a knowledge of the "why and wherefore" of the different processes required in cooking, they will have little difficulty in following the more elaborate recipes given in the numberless cook-books provided for household use. Once the art—and it is a fine art—of cookery is mastered, it becomes not only a pleasant occupation but provides excellent mental exercise, thereby preventing the reaction which frequently follows school life.
The tables given are to be used for reference, and not to be memorized by the pupil.
The writer is greatly indebted to Prof. Atwater for his kindly interest and assistance in providing much valuable information, which in some instances is given verbatim; also to Dr. Gilman Thompson for permission to give extracts from his valuable book, "Practical Dietetics"; to Prof. Kinne, Columbia University (Domestic Science Dept.), for review and suggestions; to Miss Watson, Principal Hamilton School of Domestic Science, for practical hints and schedule for school work. The Boston Cook Book (with Normal Instruction), by Mrs. M.J. Lincoln; and the Chemistry of Cooking and Cleaning, by Ellen H. Richards (Prof. of Sanitary Science, Boston Institute of Technology), and Miss Talbot, are recommended to students who desire further information on practical household matters. The publications of the U.S. Experiment Stations, by Prof. Atwater and other eminent chemists, contain much valuable information.
To the school-girls, and future housekeepers of Ontario, this book is respectfully dedicated.
"EASTCOURT," Hamilton, June, 1898.
 S.S. Laurie, A.M., LL.D., Prof. of the Institutes and History of Education, Edinburgh University.
 Where time is allowed, much benefit may be derived from writing notes, as a study in composition, spelling, etc.
SUGGESTIONS TO TEACHER.
Owing to the limitations of a text-book, it will be necessary for the teacher to enter very carefully into all the details of the various questions; to explain the underlying principles so thoroughly that "the why and the wherefore" of every action in the preparation of food will be clearly understood. She should endeavor to impress upon the pupils the value of thoroughly understanding the relation of food to the body. In practice lessons frequent reference should be made to the analysis of the various foods, as given in the tables and charts.
The first practice lesson should be given on the making and care of a fire, regulating dampers, cleaning stove, etc. The pupils should then be taught the name and place of all the utensils. Special attention should be given to the explanation of weights and measures; the table of abbreviations should be memorized. Arrange the class work so that each pupil may in alternation share the duties of both kitchen work and cooking.
Personal cleanliness must be insisted upon. Special attention should be given to the hands and nails. The hair should be carefully pinned back or confined in some way, and covered by a cap. A large clean apron and a holder should be worn while at work. Never allow the pupils to use a handkerchief or their aprons in place of a holder. Untidy habits must not be allowed in the class-room. Set an example of perfect order and neatness, and insist upon pupils following that example. Teach the pupils that cooking may be done without soiling either hands or clothes. The pupils should do all the work of the class-room, except scrubbing the floor. Everything must be left in perfect order at the close of each lesson.
Frequent reviews are absolutely necessary. Urge the pupils to think for themselves, and not to rely upon the text-book. Where pupils are backward, or have not had previous practice in kitchen work, give special attention to their manner of holding a knife or spoon in preparing articles for use, and in beating or stirring mixtures. Encourage deftness and light handling of kitchen ware. Insist upon promptness and keeping within the time limit, both in preparing the food and in the cooking.
Owing to the variety of climate and markets, it would be impossible to arrange the lessons in the text-book in regular order. A few sample menus are given at the back of the book, but each teacher must be governed by circumstances in arranging the lessons for her class. For instance, recipes without eggs should be given in mid-winter, when eggs are dear. Fruits and vegetables must be given in season.
The recipes given in the text-book are suitable for class work; in some cases it may be necessary to divide them, as the quantities given are intended for home practice. The teacher should consider herself at liberty to substitute any recipe which she may consider valuable. The digestibility of food, the effect of stimulants—especially of tea and coffee, the value of fresh air, etc., should be carefully impressed upon the pupil.
The teacher must keep the object of this instruction constantly before her: (1) to co-ordinate other school studies, such as arithmetic, history, geography, physiology and temperance; (2) to develop the mental in conjunction with the manual powers of the children; (3) to enable pupils to understand the reason for doing certain things in a certain way; in other words, to work with an intelligent conception of the value, both physically and hygienically, of knowing how the daily duties should be performed.
In order that material may not be needlessly destroyed, each class of food should be introduced by an experimental lesson. For instance, before giving a lesson in the preparation of starches, each pupil should be given an opportunity to learn how to mix and stir the mixture over the fire, so as to prevent it from burning or becoming lumpy; this may be done by using water and common laundry starch, or flour. The same test applies to sauces, etc. A few cheap apples and potatoes may be used in learning to pare these articles. The effect of cold and hot water on albumen and tissues may be illustrated by the cheaper pieces of meat.
Although the more scientific studies are grouped together, it does not follow that they are to be studied in the order given. The teacher must arrange her lessons—from the beginning—so as to include a certain amount of the theory with the practice work. Frequent reference should be made during practice lessons to the various chapters bearing more directly upon the science of cooking, so as to interest the pupil in the theoretical study of the food question.
The teacher should insist upon the pupils taking careful notes while she is demonstrating a lesson, so that they may not be entirely dependent upon the text-book, which from its limitations must simply serve as the key-note for further study.
Special attention must be given to the chapter on "Digestion," page 58, in the Public School Physiology. This chapter should be studied—especially pages 71-75—in conjunction with "Food Classifications" (Chap. 2); also in dealing with the digestibility of starches, etc.
COMPOSITION OF FOOD MATERIALS—(Atwater)
Nutritive Ingredients, Refuse, and Food Value.
Nutrients: P—Protein. F—Fats. C—Carbohydrates. M—Mineral Matters.
Non-nutrients: W—Water. R—Refuse.
Fuel Value: X—Calories.
Protein Compounds, e.g., lean of meat, white of egg, casein (curd) of milk, and gluten of wheat, make muscle, blood, bone, etc.
Fats, e.g., fat of meat, butter, and oil, serve as fuel to yield / heat and muscular power. Carbohydrates, e.g., starch and sugar, /
Nutrients, etc., p.c 10 20 30 40 50 60 70 80 90 100 -+ - Fuel value of 1 lb. 400 800 1200 1600 2000 2400 2800 3200 3600 4000 -+ PPPPPPP FFFF M WWWWWWWWWWWWWWWWWWWWWWWWWWWWWW RRR Beef, round XXXXXXXXX -+ PPPPPPPPP FFFFF M WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW Beef, round[A] XXXXXXXXXX -+ PPPPPPP FFFFFFFF M WWWWWWWWWWWWWWWWWWWWWWWWW RRRR Beef, sirloin XXXXXXXXXXXXX -+ PPPPPPPP FFFFFFFF M WWWWWWWWWWWWWWWWWWWWWWWWWWWWW Beef, sirloin[A] XXXXXXXXXXXXXXX -+ PPPPPP FFFFFFFF M WWWWWWWWWWWWWWWWWWWW RRRRRRRRRR Beef, rib XXXXXXXXXXXXX -+ PPPPPPPP FFFFFFFFFFFF M WWWWWWWWWWWWWWWWWWWWWWWWW Beef, rib[A] XXXXXXXXXXXXXXXXXX -+ PPPPPPP FFFFFF M WWWWWWWWWWWWWWWWWWWWWWWW RRRRRRR Mutton, leg XXXXXXXXXXX -+ PPPPPP FFFFFFFFFF M WWWWWWWWWWWWWWWWWWWWWW RRRRRR Pork, spare rib XXXXXXXXXXXXXXXX -+ PP FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF MM WWWWWW RRR Pork, salt XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX -+ PPP FFFFFFFFFFFFFFFFF MM WWWWWWWWWWWWWWWWW RRRRRR Ham, smoked XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX -+ PPPPP M WWWWWWWWWWWWWWWWWWWWWWWWWWW RRRRRRRRRRRRR Codfish, fresh XXX -+ PPPPPPPP MMMMMMM WWWWWWWWWWWWWWWWWWWW RRRRRRRRRRR Codfish, salt XXXX -+ PP F CC M WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW Oysters XXX -+ P F CC M WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW Milk XXXX -+ P FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF C M WWWW Butter XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX -+ PPPPPPPPPPPP FFFFFFFFFFFFFFFFF C MM WWWWWWWWWWWWW Cheese XXXXXXXXXXXXXXXXXXXXXXXXX -+ PPPPP FFFF M WWWWWWWWWWWWWWWWWWWWWWWWWWWWWW RRRRR Eggs XXXXXXXX -+ PPPP F CCCCCCCCCCCCCCCCCCCCCCCCC M WWWWWWWWWWWWWW Wheat bread XXXXXXXXXXXXXXXX -+ PPPP F CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC M WWWWW Wheat flour XXXXXXXXXXXXXXXXXXXX -+ PPPP FF CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC M WWWWWW Cornmeal XXXXXXXXXXXXXXXXXXXX -+ PPPPPP FFF CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC M WW Oatmeal XXXXXXXXXXXXXXXXXXXXXX -+ PPPPPPPPPP F CCCCCCCCCCCCCCCCCCCCCCCCCCC MM WWWWW Beans, dried XXXXXXXXXXXXXXXXXXXX -+ PP F CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC M WWWWW Rice XXXXXXXXXXXXXXXXXXXX -+ P CCCC M WWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW RRRRRR Potatoes XXX -+ CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC Sugar XXXXXXXXXXXXXXXXXXXXXX -+
[A] Without bone.
PECUNIARY ECONOMY OF FOOD—(Atwater).
Amounts of actually Nutritive Ingredients obtained in different Food Materials for 10 cents.
P—Protein. F—Fats. C—Carbohydrates. X—Fuel Value.
Protein compounds, e.g., lean of meat, white of egg, casein (curd) of milk, and gluten of wheat, make muscle, blood, bone, etc.
Fats, e.g., fat of meat, butter and oil, serve as fuel to yield / heat and muscular power. Carbohydrates, e.g., starch and sugar, /
+ -+ + Price Ten per cents Pounds of Nutrients and Calories of pound. will Fuel Value in 10 cents worth. buy + -+ + Cents. Lbs. 1 Lb. 2 Lbs. 3 Lbs. 4 Lbs. 2000 Cal. 4000 Cal. 6000 Cal. 8000 Cal. + -+ + - - - - PP F Beef, round 12 .83 XXXXX + -+ + - - - - P F Beef, sirloin 18 .55 XXXXX + -+ + - - - - P F Beef, rib 16 .63 XXXXX + -+ + - - - - PP F Mutton, leg 12 .83 XXXXX + -+ + - - - - Pork, PP FF spare rib 12 .83 XXXXXX + -+ + - - - - Pork, P FFFF salt, fat 14 .71 XXXXXXXXXX + -+ + - - - - P FFF Ham, smoked 16 .63 XXXXXX + -+ + - - - - Codfish, PP fresh 8 1.25 XX + -+ + - - - - Codfish, PPP salt 6 1.67 XXX + -+ + - - - - Oysters, 40 P cents quart 20 .50 X + -+ + - - - - Milk, 6 cents P F C quart 3 3.33 XXXXXX + -+ + - - - - FFFF Butter 24 .42 XXXXXXX + -+ + - - - - PP FF Cheese 16 .63 XXXXXX + -+ + - - - - Eggs, 25 P F cents dozen 16-3/4 .60 XXX + -+ + - - - - PP F CCCCCCCCCCCC Wheat bread 4 2.50 XXXXXXXXXXXXXXXX + -+ + - - - - PPP F CCCCCCCCCCCCCCCCCCCCCCC Wheat flour 2-1/2 4.00 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + -+ + - - - - PPP FF CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC Cornmeal 2 5.00 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + -+ + - - - - PP FF CCCCCCCCCCCCCCC Oatmeal 4 2.50 XXXXXXXXXXXXXXXXXXXXXX + -+ + - - - - Beans, white, PPPP F CCCCCCCCCCCCCC dried 4 2.50 XXXXXXXXXXXXXXXXXXX + -+ + - - - - P CCCCCCCCCCCCCC Rice 5 2.00 XXXXXXXXXXXXXXX + -+ + - - - - Potatoes, 60 P CCCCCCCCCCCCCC cents bushel 1 10.00 XXXXXXXXXXXXXXX + -+ + - - - - CCCCCCCCCCCCCCCCCCC Sugar 5 2.00 XXXXXXXXXXXXXXXXXX + -+ + - - - -
PAGE. Preface v Suggestions to Teachers ix Composition of Food Materials (Atwater) xii Pecuniary Economy of Food (Atwater) xiii
CHAPTER I. The Relation of Food to the Body 1
CHAPTER II. Food Classification 6
CHAPTER III. Nutrition 10
CHAPTER IV. Food and Economy 12
CHAPTER V. Foods containing Protein or Nitrogenous Matter 22
CHAPTER VI. Fats and Oils 34
CHAPTER VII. Carbohydrate Foods 37
CHAPTER VIII. Fruits 50
CHAPTER IX. Preparing Food 54
RECIPES: Batters, Biscuits and Bread 60 Bread 65 Sauces and Milk Soups 66 Eggs 69 Fruit 72 Vegetables 74 Salads 80 Macaroni 85 Cheese 86 Beverages 87 Soups 89 Fish 94 Meat 96 Poultry 104 Hot Puddings 109 Plain Sauces 115 Pastry 121 Miscellaneous 122
General Hints 126
Suggestions for Young Housekeepers 128
Caring for Invalids 142
General Hints for School Children 150
Suggestions for School Children's Diet 153
Infants' Diet 156
Planning and Serving Meals 170
Consideration of Menus 173
Suggestive Questions 188
Schedule of Lessons for Public School Classes 191
PUBLIC SCHOOL DOMESTIC SCIENCE
The Relation of Food to the Body.
In order to understand the relation of food to the sustenance and repairing of the body, it will be necessary to learn, first, of what the body is composed, and the corresponding elements contained in the food required to build and keep the body in a healthy condition. The following table gives the approximate analysis of a man weighing 148 pounds:—
Oxygen 92.1 pounds. Hydrogen 14.6 " Carbon 31.6 " Nitrogen 4.6 " Phosphorus 1.4 " Calcium 2.8 " Sulphur 0.24 " Chlorine 0.12 " Sodium 0.12 " Iron 0.02 " Potassium 0.34 " Magnesium 0.04 " Silica ? " Fluorine 0.02 " ——— Total 148.00 pounds.
As food contains all these elements, and as there is constant wearing and repair going on in the body, it will be readily seen how necessary some knowledge of the relation of food to the body is, in order to preserve health.
Hydrogen and oxygen combined form water, hence we find from the above calculation that about three-fifths of the body is composed of water. Carbon is a solid: diamonds are nearly pure carbon; "lead" of lead pencils, anthracite coal and coke are impure forms of carbon. Carbon combined with other elements in the body makes about one-fifth of the whole weight. Carbon with oxygen will burn. In this way the carbon taken into the body as food, when combined with the oxygen of the inhaled air, yields heat to keep the body warm, and force—muscular strength—for work. The carbonic acid (or carbon dioxide) is given out through the lungs and skin. In the further study of carbonaceous foods, their relation to the body as fuel will be more clearly understood, as carbon is the most important fuel element. Phosphorus is a solid. According to the table, about one pound six ounces would be found in a body weighing 148 pounds. United with oxygen, phosphorus forms what is known as phosphoric acid; this, with lime, makes phosphate of lime, in which form it is found in the bones and teeth; it is found also in the brain and nerves, flesh and blood. Hydrogen is a gas, and like carbon unites with the oxygen of the inhaled air in the body, thus serving as fuel. The water produced is given off in the respiration through the lungs and as perspiration through the skin. Calcium is a metal. The table given allows three pounds of calcium; united with oxygen, calcium forms lime. This with phosphoric acid makes phosphate of lime, the basis of the bones and teeth, in which nearly all the calcium of the body is found.
The elements which bear no direct relation to the force production of the body, but which enter into tissue formation, are chlorine, sulphur, iron, sodium, potassium, phosphorus, calcium and magnesium. Bone tissue contains about 50 per cent. of lime phosphate, hence the need of this substance in the food of a growing infant, in order that the bones may become firm and strong. Lack of iron salts in the food impoverishes the coloring matter of the red blood corpuscles on which they depend for their power of carrying oxygen to the tissues; anaemia and other disorders of deficient oxidation result. The lack of sufficient potash salts is a factor in producing scurvy, a condition aggravated by the use of common salt. A diet of salt meat and starches may cause it, with absence of fresh fruit and vegetables. Such illustrations show the need of a well-balanced diet.
In order to understand the value of the various classes of food and their relation to the body as force producers, tissue builders, etc., the following table may prove helpful:—
C.H. Combustibles Nitrogen. Calculated as Carbon. - - Beef, uncooked 3.00 11.00 Roast beef 3.53 17.76 Calf's liver 3.09 15.68 Foie-gras 2.12 65.58 Sheep's kidneys 2.66 12.13 Skate 3.83 12.25 Cod, salted 5.02 16.00 Herring, salted 3.11 23.00 Herring, fresh 1.83 21.00 Whiting 2.41 9.00 Mackerel 3.74 19.26 Sole 1.91 12.25 Salmon 2.09 16.00 Carp 3.49 12.10 Oysters 2.13 7.18 Lobster, uncooked 2.93 10.96 Eggs 1.90 13.50 Milk (cows') 0.66 8.00 Cheese (Brie) 2.93 35.00 Cheese (Gruyere) 5.00 38.00 Cheese (Roquefort) 4.21 44.44 Chocolate 1.52 58.00 Wheat (hard Southern, variable average) 3.00 41.00 Wheat (soft Southern, variable average) 1.81 39.00 Flour, white (Paris) 1.64 38.50 Rye flour 1.75 41.00 Winter barley 1.90 40.00 Maize 1.70 44.00 Buckwheat 2.20 42.50 Rice 1.80 41.00 Oatmeal 1.95 44.00 Bread, white (Paris, 30 per cent. water) 1.08 29.50 Bread, brown (soldiers' rations formerly) 1.07 28.00 Bread, brown (soldiers' rations at present) 1.20 30.00 Bread, from flour of hard wheat 2.20 31.00 Potatoes 0.33 11.00 Beans 4.50 42.00 Lentils, dry 3.87 43.00 Peas, dry 3.66 44.00 Carrots 0.31 5.50 Mushrooms 0.60 4.52 Figs, fresh 0.41 15.50 Figs, dry 0.92 34.00 Coffee (infusion of 100 grams) 1.10 9.00 Tea (infusion of 100 grams) 1.00 10.50 Bacon 1.29 71.14 Butter 0.64 83.00 Olive oil Trace 98.00 Beer, strong 0.05 4.50 Wine 0.15 4.00 - -
"The hydrogen existing in the compound in excess of what is required to form water with the oxygen present is calculated as carbon. It is only necessary to multiply the nitrogen by 6.5 to obtain the amount of dry proteids in 100 grams of the fresh food substance." (Dujardin-Beauretz.) The following simple rules are given by Parks:—"1st. To obtain the amount of nitrogen in proteid of foods, divide the quantity of food by 6.30. 2nd. To obtain the carbon in fat multiply by 0.79. 3rd. To obtain the carbon in carbohydrate food multiply by 0.444. 4. To obtain the carbon in proteid food multiply by 0.535."
Finding that our food and our bodies contain essentially the same elements, we must also bear in mind that the body cannot create anything for itself, neither material nor energy; all must be supplied by the food we eat, which is transformed into repair material for the body. Therefore, the object of a course of study dealing with the science of this question, as it relates to the daily life, should be to learn something of how food builds the body, repairs the waste, yields heat and energy, and to teach the principles of food economy in its relation to health and income. This, with the development of executive ability, is all that can be attempted in a primary course.
 An illustration of vapor rising may be given by breathing upon a mirror.
The following are familiar examples of compounds of each of the four principal classes of nutrients:
Albuminoids, e.g., albumen of eggs; myosin, the basis of muscle (lean meat); the albuminoids which make up the gluten of wheat, etc.
Gelatinoids, constituents of connective tissue which yield gelatin and allied substances, e.g., collagen of tendon; ossein of bone.
"Nitrogenous extractives" of flesh, i.e., of meats and fish. These include kreatin and allied compounds, and are the chief ingredients of beef tea and most meat extracts. Amids: this term is frequently applied to the nitrogenous non-albuminoid compounds of vegetable foods and feeding stuffs, among which are amido acids, such as aspartic acid and asparagin. Some of them are more or less allied in chemical constitution to the nitrogenous extractives of flesh.
Fat of meat: fat of milk; oil of corn, wheat, etc. The ingredients of the "ether extract" of animal and vegetable foods and feeding stuffs, which it is customary to group together roughly as fats, include, with the true fats, various other substances, as lecithians, and chlorophylls.
Carbohydrates, sugars, starches, celluloses, gums, woody fibre, etc.
Potassium, sodium, calcium and magnesium chlorids, sulphates and phosphates. (Atwater).
The terms (a) "nitrogenous" and (b) "carbonaceous" are frequently used to designate the two distinct classes of food, viz.: (a) the tissue builders and flesh formers; (b) fuel and force producers.
Each of these classes contains food material derived from both the animal and vegetable kingdom, although the majority of the animal substances belong to the nitrogenous, and the majority of the vegetable substances to the carbonaceous group.
Therefore, for practical purposes, we will confine ourselves to the more general terms used in Atwater's table.
Uses of Food.
First, food is used to form the materials of the body and repair its waste; second, to yield energy in the form of (1) heat to keep the body warm, (2) to provide muscular and other power for the work it has to do. In forming the tissues and fluids of the body the food serves for building and repair. In yielding energy, it serves as fuel for heat and power. The principal tissue formers are the albuminoids; these form the frame-work of the body. They build and repair the nitrogenous materials, as those of muscle, tendon and bone, and supply the albuminoids of blood, milk and other fluids. The chief fuel ingredients of food are the carbohydrates and fats. These are either consumed in the body or are stored as fat to be used as occasion demands.
By referring to a preceding chapter we find that water composes three-fifths of the entire body. The elasticity of muscles, cartilage, tendons, and even of bones is due in great part to the water which these tissues contain. The amount of water required by a healthy man in twenty-four hours (children in proportion) is on the average between 50 and 60 ounces, beside about 25 ounces taken as an ingredient of solid food, thus making a total of from 75 to 85 ounces. One of the most universal dietetic failings is neglect to take enough water into the system. Dr. Gilman Thompson gives the following uses of water in the body:—
(1) It enters into the chemical composition of the tissues; (2) it forms the chief ingredient of all the fluids of the body and maintains their proper degree of dilution; (3) by moistening various surfaces of the body, such as the mucous and serous membranes, it prevents friction and the uncomfortable symptoms which might result from drying; (4) it furnishes in the blood and lymph a fluid medium by which food may be taken to remote parts of the body and the waste matter removed, thus promoting rapid tissue changes; (5) it serves as a distributer of body heat; (6) it regulates the body temperature by the physical processes of absorption and evaporation.
Salts (Mineral Matter).—Use of Salts in Food.
(1) To regulate the specific gravity of the blood and other fluids of the body; (2) to preserve the tissues from disorganization and putrefaction; (3) to enter into the composition of the teeth and bones. These are only a few of the uses of salts in the body, but are sufficient for our purpose. Fruits and nuts contain the least quantity of salts, meat ranks next, then vegetables and pulses, cereals contain most of all (Chambers). Sodium chloride (common salt) is the most important and valuable salt. It must not however be used in excess. Potassium salts rank next in importance. Calcium, phosphorus, sulphur and iron are included in this class.
The quantity of salts or mineral matter contained in some important articles of vegetable and animal food is shown in this table (Church):
Mineral Matter in 1,000 lbs. of 14 Vegetable Products.
Lbs. Apples 4 Rice 5 Wheaten flour 7 Turnips 8 Potatoes 10 Barley 11 Cabbage 12 Bread 12 Watercress 13 Maize 20 Oatmeal 21 Peas 30 Cocoa nibs 36 Wheaten bran 60
Mineral Matter in 1,000 lbs. of 8 Animal Products.
Lbs. Fat Pork 5 Cow's milk 7 Eggs (without shells) 13 Lean of mutton 17 Flesh of common fowl 16 Bacon 44 Gloucester cheese 49 Salted herrings 158
"In most seeds and fruits there is much phosphate in the mineral matter, and in most green vegetables much potash. One important kind of mineral matter alone is deficient in vegetable food, and that is common salt."
 See Vegetables, Chap. VII.
It is not within the scope of this book to deal with the science of nutrition; but a few general principles may be given which concern the effect upon the system of the different classes of food. Animal food requires a considerable quantity of oxygen for its complete combustion. Meat in general has a more stimulating effect upon the system and is more strengthening than vegetable food. There is, however, a tendency to eat too much meat, and when its effects are not counter-balanced by free outdoor exercise, it causes biliousness and sometimes gout and other troubles. Albuminous foods can be eaten longer alone without exciting loathing than can fats, sugars or starches. A carbonaceous diet taxes the excretory organs less than animal food. Meat is not necessary to life. Nitrogenous food man must have, but it need not be in the form of meat. The estimate commonly given is, that meat should occupy one-fourth and vegetable food three-fourths of a mixed diet, but in many cases the meat eaten is much in excess of this allowance. The proper association of different foods always keeps healthy people in better condition; there are times, however, when it may be necessary to abstain from certain articles of diet. It may be well to bear in mind, that the protein compounds can do the work of the carbohydrates and fats in being consumed for fuel, but the carbohydrates and fats cannot do the work of protein in building and repairing the tissues of the body. As already stated, a mixed diet is the only rational one for man. An exclusively vegetable diet, while it may maintain a condition of health for a time, eventually results in a loss of strength and power to resist disease. Therefore it is necessary to understand the approximate value of each class of food in arranging the daily dietary.
Food and Economy.
It has been stated that "a quart of milk, three-quarters of a pound of moderately lean beef, and five ounces of wheat flour contain about the same amount of nutritive material;" but we pay different prices for them, and they have different values for nutriment. The milk comes nearest to being a perfect food. It contains all the different kinds of nutritive materials that the body requires. Bread made from wheat flour will support life. It contains all the necessary ingredients for nourishment, but not in the proportion best adapted for ordinary use. A man might live on beef alone, but it would be a very one-sided and imperfect diet. Meat and bread together make the essentials of a healthful diet. In order to give a general idea of food economy, it will be necessary to deal briefly with the functions of the various food principles. As our bodies contain a great deal of muscle, the waste of which is repaired by protein found in such food as lean meat, eggs, cheese, beans, peas, oatmeal, fish, etc., a supply of these articles must be considered in purchasing the daily supply. Fatty tissue (not muscle) serves as fuel, therefore the value of such foods as butter, cream, oils, etc., is apparent. Carbohydrates form fat and serve as fuel and force producers; these come in the form of starches, sugars,—vegetables and grains being the most important. In being themselves burned to yield energy, the nutrients protect each other from being consumed. The protein and fats of body tissue are used like those of foods. An important use of the carbohydrates and fats is to protect protein (muscle, etc.) from consumption. "The most healthful food is that which is best fitted to the wants of the user: the cheapest food is that which furnishes the largest amount of nutriment at the least cost: the best food is that which is both healthful and cheap." By referring to the various charts a fair estimate of food values may be obtained.
As will be noticed, the animal foods contain the most protein and fats, while the vegetable foods are rich in carbohydrates. A pound of cheese may have 0.28 pound of protein, as much as a man at ordinary work needs for a day's sustenance, while a pound of milk would have only 0.04, and a pound of potatoes 0.02 pound of protein. The materials which have the most fats and carbohydrates have the highest fuel value. The fuel value of a pound of fat pork may reach 2.995 calories, while that of a pound of salt codfish would be only .315 calories. On the other hand, the nutritive material of the codfish would consist almost entirely of protein, while the pork contains very little. Among the vegetable foods, peas and beans have a high proportion of protein. Oatmeal contains a large proportion also. Potatoes are low in fuel value as well as in protein, because they are three-fourths water. For the same reason milk, which is seven-eights water, ranks low in respect to both protein and fuel value, hence the reason why it is not so valuable as food for an adult as many of the other food materials.
These few illustrations will help to show the need of an intelligent idea of food values before attempting to purchase the supplies for family use. As one-half a laboring man's income goes towards providing food, it must follow that such knowledge will help the housewife very materially in securing the best results from the amount expended.
The average daily diet of an adult should contain (Church):—
- NUTRIENTS. IN 100 PARTS. EACH 24 HOURS. - lb. oz. gr. Water 81.5 5 8 .320 Albuminoids 3.9 0 4 .178 Fat 3.0 0 3 .337 Common salt 3.7 0 0 .325 Phosphates, potash, salts, etc. 0.3 0 0 0.170 -
Quantity of Food Required.
The quantity of food required to maintain the body in a vigorous condition depends upon the following conditions:—(1) Climate and season, (2) clothing, (3) occupation, (4) age and sex. In civilized countries more food is eaten, as a rule, than is necessary to maintain health and strength. Climate and seasons influence the quantity of food eaten. A cold, bracing atmosphere stimulates the appetite, tempts one to exercise, while a hot climate has the contrary effect; hence the need for more or less food. Abundant clothing in cold weather conserves the body heat; less food is therefore required to maintain life. Exercise and muscular work cause greater oxidation in the tissues and greater waste of the muscles; this must be replaced by proper food. Outdoor work requires more food than indoor, and physical labor more than mental. It has been estimated "that a child of ten years requires half as much food as a grown woman, and one of fourteen an equal amount. The rapidly growing active boy often eats as much as a man, and the middle-aged man requires more than the aged. A man of seventy years may preserve health on a quantity which would soon starve his grandson."
Just what ingredients of the food serve for nourishment of the brain and nerves, and how they do that service, are mysteries which have not yet been solved. Brain and nerve contain the elements nitrogen and phosphorus, which are found in protein compounds but not in the true fats, sugars, and starches, which contain only carbon, hydrogen and oxygen. We naturally infer that the protein compounds must be especially concerned in building up brain and nerve, and keeping them in repair. Just how much food the brain worker needs is a question which has not yet been decided. In general it appears that a man or a woman whose occupation is what we call sedentary, who is without vigorous exercise and does but little hard muscular work, needs much less than the man at hard manual labor, and that the brain worker needs comparatively little of carbohydrates or fats. Many physicians, physiologists and students of hygiene have become convinced that well-to-do people, whose work is mental rather than physical, eat too much; that the diet of people of this class as a whole is one-sided as well as excessive, and that the principal evil is the use of too much fat, starch and sugar. It is well to remember that it is the quantity of food digested which builds the body, and more injury is likely to result from over-eating than from a restricted diet, hence the value of having food cooked so as to aid digestion. The following dietary standards may be interesting to the more advanced pupils, housewives, etc.:—
STANDARDS FOR DAILY DIET OF LABORING MAN AT MODERATE MUSCULAR WORK.
================================================================= Nutrients in Daily Food. Author. Protein. Fats. - Carbohydrates. Fuel Value. - - lb. lb. lb. Calories. Playfair, England .26 .11 1.17 3.140 Moleschotte, Italy .29 .09 1.21 3.160 Wolff, Germany .28 .08 1.19 3.030 Voit, Germany .26 .12 1.10 3.055 Atwater, United States .28 17.33 88.1.21 3.500 - -
Quality of Food.
It is a great mistake to think that the best is the cheapest in regard to the food question, that the higher priced meats, fish, butter, etc., contain special virtues lacking in the cheaper articles. Poor cooking is the chief cause of this error in judgment. No doubt a well broiled steak is more appetizing and delicate in flavor than some of the cheaper cuts, but in proportion to the cost is not equal in nutritive value; careful cooking and judicious flavoring render the cheaper pieces of beef equally palatable. That expensive food is not necessary to maintain life has been clearly demonstrated by the traditional diet of the Scotch people with their oatmeal and herring; the Irish, potatoes and buttermilk; New England, codfish and potatoes, and pork and beans; the Chinese, rice, etc. Monotony of diet, however, is not recommended, for reasons given in a previous chapter, and in the countries where a special diet prevails owing to the climate, nature of soil and markets, the results have not warranted us in believing that it is as good as a mixed diet. From this necessarily brief outline of the food question we have learned (1) that a knowledge of the requirements of the body are absolutely necessary in regulating a proper diet; (2) to furnish the food principles in a cheap rather than a dear form; (3) to understand the art of cookery so as to secure the full nutritive value and at the same time stimulate the appetite; (4) the value of economy in regard to food principles. When the housekeeper has acquired this knowledge she will have covered the field of food economy. Prof. Atwater says: "When we know what are the kinds and amount of nutritive substances our bodies need and our food materials contain, then and not till then shall we be able to adjust our diet to the demands of health and purse."
Cooking of Food.
It is sometimes asked, why do we cook our food? As many opportunities will occur during this course of instruction for a comparison of the customs and diet of the various countries, and the advance of civilization in this direction, we will confine ourselves to the definition of the term as it concerns ourselves.
Mr. Atkinson says, that "Cooking is the right application of heat for the conversion of food material."
As much of our food requires cooking, how we shall cook it so as to render it more palatable, more digestible, and with the greatest economy of time, fuel and money, is an object deserving the most careful attention. The art of cooking lies in the power to develop certain flavors which are agreeable to the palate, or in other words, which "make the mouth water," without interfering with the nutritive qualities of the food prepared, to understand by what method certain foods may be rendered more digestible, and to provide variety. Monotony of diet and of flavor lessens the appetite and fails to stimulate the digestive organs.
The chemical changes, produced by cooking food properly, aid digestion, beside destroying any germs which may be contained in the food. Nearly all foods—except fruit—require cooking. The digestibility of starch depends almost entirely upon the manner in which it is cooked, especially the cereal class. Gastric troubles are sure to follow the use of improperly cooked grains or starches. (See Chap. VII.)
The following are the usual methods observed in cooking, viz.: (1) boiling, (2) stewing, (3) roasting, (4) broiling, (5) frying, (6) braising, (7) baking, (8) steaming.
Water boils at a temperature of 212 deg. F. Simmering should be at a temperature of from 175 deg. F. to 180 deg. F. When water has reached the boiling point, its temperature cannot be raised, but will be converted into steam; hence the folly of adding fuel to the fire when water has already reached the boiling point.
Stewing allows the juices of the meat to become dissolved in water heated to the simmering point. The juices thus dissolved are eaten with the meat. If not injured by the addition of rich sauces or fats, this is usually a very digestible method of preparing certain kinds of meat.
Broiling is cooking directly over the hot coals. A coating of coagulated albumen is formed upon the outer surface. This coating prevents the evaporation of the juices, which with the extractive materials are retained and improve the flavor. Meat cooked in this way has a decided advantage, in both flavor and nutritive value, over that which has been boiled or stewed. There are, however, only certain kinds of meat that are suitable for broiling.
Frying is cooking in hot fat. The boiling point of fat is far above that of water. Fat should not be heated above 400 deg. F., as it will then turn dark and emit a disagreeable odor. Fried food, unless very carefully prepared, is considered unwholesome. The only proper method for frying is to immerse the food completely in a bath of hot fat.
Braising is cooking meat in a covered vessel surrounded by a solution of vegetable and animal juices in a strong but not boiling temperature. Tough meat may be rendered very palatable and nutritious by cooking in this way. The cover of the pan or kettle must fit closely enough to prevent evaporation. It requires long, steady cooking. The flavor is improved by browning the meat in either hot fat or in a very hot oven before braising.
Baking is cooking in confined heat. Meat properly cooked in an oven is considered by many authorities as quite equal in delicacy of flavor to that roasted before a fire, and is equally digestible.
Steaming is cooking food over condensed steam, and is an excellent method for preparing food which requires long, slow cooking. Puddings, cereals, and other glutinous mixtures are often cooked in this way. It is an economical method, and has the advantage of developing flavor without loss of substance.
Food is preserved by the following processes: (1) drying, (2) smoking, (3) salting, (4) freezing, (5) refrigerating, (6) sealing, (7) addition of antiseptic and preservative substances.
Drying in the sun and before a fire is the usual method employed by housekeepers. Fruits and vegetables, meat and fish may be preserved by drying, the latter with the addition of salt.
Smoking is chiefly applied to beef, tongue, bacon, ham, and fish, which are hung in a confined chamber, saturated with wood smoke for a long time until they absorb a certain percentage of antiseptic material, which prevents the fat from becoming rancid, and the albumen from putrefying. Well smoked bacon cut thin and properly cooked is a digestible form of fatty food, especially for tubercular patients. Smoking improves the digestibility of ham.
Salting is one of the oldest methods of preserving food. The addition of a little saltpetre helps to preserve the color of the meat. Brine is frequently used to temporarily preserve meat and other substances. Corned beef is a popular form of salt preservation. All salted meats require long, slow cooking. They should always be placed in cold water and heated gradually in order to extract the salt. Salt meats are less digestible and not quite so nutritious as fresh meats.
Food may be kept in a frozen condition almost indefinitely, but will decompose very quickly when thawed, hence the necessity for cooking immediately. Frozen meat loses 10 per cent. of its nutritive value in cooking.
This process does not involve actual freezing, but implies preservation in chambers at a temperature maintained a few degrees above freezing point. This method does not affect the flavor or nutritive value of food so much as freezing.
Sealing is accomplished not only in the process of canning but by covering with substances which are impermeable. Beef has been preserved for considerable time by immersing in hot fat in which it was allowed to remain after cooling.
Chemicals are sometimes used in the preservation of food, but the other methods are safer.
Foods Containing Protein, or Nitrogenous Matter.
Animal foods contain nutritive matter in a concentrated form, and being chemically similar to the composition of the body is doubtless the reason why they assimilate more readily than vegetable foods, although the latter are richer in mineral matter. The most valuable animal foods in common use are meat, eggs, milk, fish, gelatin and fats.
Meat is composed of muscular tissue, connective tissue or gristle, fatty tissue, blood-vessels, nerves, bone, etc. The value of meat as food is due chiefly to the nitrogenous compound it contains, the most valuable being the albuminoids: the gelatinoid of meat is easily changed into gelatin by the action of hot water. Gelatin when combined with the albuminoids and extractives has considerable nutritive value. Extractives are meat bases, or rather meat which has been dissolved by water, such as soup stock and beef tea. The object in cooking meat is to soften and loosen the tissue, which renders it more easily digested. Another object is to sterilize or kill any germs which may exist and to make it more palatable. The digestibility of meat is influenced by the age of the animal killed and the feeding. The following table is given as an average of the digestibility of animal foods:—
TABLE OF COMPARATIVE DIGESTIBILITY.
Commencing with the most digestible and ending with the least digestible of meats and other animal foods. (Thompson.)
Oysters. Soft cooked eggs. Sweetbread. Whitefish, etc. Chicken, boiled or broiled. Lean roast beef or beefsteak. Eggs, scrambled, omelette. Mutton. Bacon. Roast fowl, chicken, turkey, etc. Tripe, brains, liver. Roast lamb. Chops, mutton or lamb. Corn beef. Veal. Duck and other game. Salmon, mackerel, herring. Roast goose. Lobster and crabs. Pork. Fish, smoked, dried, pickled.
Cooking affects the digestibility of meat, which is evident from the figures given in the following table (Church):—
TIME OF DIGESTION.
+ Hours. + Beef, raw 2 Beef, half boiled 2-1/2 Beef, well boiled 2-3/4 to 3 Beef, half roasted 2-3/4 to 3 Beef, well roasted 2-1/4 to 4 Mutton, raw 2 Mutton, boiled 3 Mutton, roasted 3-1/4 Veal, raw 2-1/2 Pork, raw 3 Pork, roasted 5-1/4 Fowl, boiled 4 Turkey, boiled 2-1/2 Venison, broiled 1-1/2 +
It may be well to add here that animal food is more digestible when cooked between 160 deg. and 180 deg. F. than at a higher temperature.
Cooking of Meat.
(For more general information, see Recipes.)
In boiling meat two principles must be considered, the softening of the fibre and preserving of the juices. If the meat alone is to be used it should be placed in sufficient boiling water to completely cover, and kept at boiling point (212 deg. F.) for at least ten minutes, so as to harden the albumen and prevent the escape of the juices. The temperature should then be allowed to fall to simmering point (175 deg. F.). If the water is kept boiling it will render the meat tough and dry. If the juice is to be extracted and the broth used, the meat should be placed in cold water; if bones are added they should be cut or broken into small pieces in order that the gelatin may be dissolved. If the water is heated gradually the soluble materials are more easily dissolved. The albumen will rise as a scum to the top, but should not be skimmed off, as it contains the most nutriment and will settle to the bottom as sediment.
If both meat and broth are to be used the process of cooking should be quite different. In stewing, the meat should be cut into small pieces, put into cold water in order that the juices, flavoring material and fibre may be dissolved. The temperature should be gradually raised to simmering point and remain at that heat for at least three or four hours, the vessel being kept closely covered. Cooked in this way the broth will be rich, and the meat tender and juicy. Any suitable flavoring may be added. This is a good method for cooking meat containing gristle.
ROASTING AND BROILING.
When the meat alone is to be eaten, either roasting, broiling or frying in deep fat is a more economical method, as the juices are saved. The shrinkage in a roast of meat during cooking is chiefly due to a loss of water. A small roast will require a hotter fire than a larger one, in order to harden the exterior and prevent the juices from escaping. Meat is a poor conductor of heat, consequently a large roast exposed to this intense heat would become burned before the interior could be heated. The large roast should be exposed to intense heat for a few minutes, but the temperature should then be reduced, and long steady cooking allowed.
Broiling (see broiling in previous chapter, p. 19.)
Varieties of Meat.
Beef tongue is a tender form of meat, but contains too much fat to agree well with people of delicate digestion.
Veal, when obtained from animals killed too young, is apt to be tough, pale and indigestible, but good veal is considered fairly nutritious. It contains more gelatin than beef, and in broth is considered valuable, especially for the sick.
Mutton is considered to be more digestible than beef, that is well fed mutton from sheep at least three years old; but as it is more difficult to obtain tender mutton than beef, the latter is more generally preferred. Mutton broth is wholesome and valuable in sickness.
Lamb, when tender and of the right age, is quite as digestible as beef or mutton, but the flesh contains too large a proportion of fat.
Venison is a tender meat with short fibres, which is very digestible when obtained from young deer, but is considered to be rather too stimulating. Its chemical composition is similar to lean beef.
Pork is a tender-fibred meat, but is very indigestible owing to the high percentage of fat, which is considerably more than the nitrogenous material it contains. Pork ribs may have as much as 42 per cent. of fat.
HAM AND BACON.
Ham is more digestible when well boiled and eaten cold. Bacon is more easily digested than either ham or pork; when cut thin and cooked quickly—until transparent and crisp—it can often be eaten by dyspeptics, and forms an excellent food for consumptives.
Chicken is one of the most digestible of meats, contains considerable phosphorus and is particularly valuable as food for invalids. Turkey is somewhat less digestible than chicken. Ducks and geese are difficult of digestion, unless quite young, on account of the fat they contain.
Game, if well cooked, is fairly digestible.
Sweetbread, which is thymus gland of the calf, is a delicate and agreeable article of diet, particularly for invalids. Tripe, heart, liver and kidneys are other forms of animal viscera used as food—valuable chiefly as affording variety.
The chief difference in fish is the coarseness of fibre and the quantity of fat present. Fish which are highly flavored and fat, while they may be nutritious, are much less easy of digestion than flounder, sole, whitefish, and the lighter varieties. The following fish contain the largest percentage of albuminoids:—Red snapper, whitefish, brook trout, salmon, bluefish, shad, eels, mackerel, halibut, haddock, lake trout, bass, cod and flounder. The old theory that fish constituted "brain food," on account of the phosphorus it contained, has proved to be entirely without foundation, as in reality many fish contain less of this element than meat. The tribes which live largely on fish are not noted for intellectuality. Fish having white meat when broiled or boiled—not fried—are excellent food for invalids or people of weak digestion. Fish should be well cooked.
Oysters are a nutritious food, and may be eaten either raw or cooked. Lobsters, crabs and shrimps are called "sea scavengers," and unless absolutely fresh are not a desirable food.
Milk contains all the elements which are necessary to maintain life; and constitutes a complete diet for infants. It will sustain life in an adult for several months. Although milk furnishes a useful food, it is not essential to a diet required for active bodily exercise. It is seldom given to athletes while in active training. Adults who are able to eat any kind of food are kept in better health by abstaining from milk, except as used for cooking purposes. An occasional glass of hot milk taken as a stimulant for tired brain and nerves is sometimes beneficial. Milk is composed of water, salts, fat, milk sugar or lactose, albumen and casein. Average milk has from 8 to 10 per cent. of cream. Good milk should form a layer of cream about 2-1/2 in. thick as it stands in a quart bottle. Lactose (milk sugar) is an important ingredient in milk. It is less liable to ferment in the stomach than cane sugar. In the presence of fermenting nitrogenous material it is converted into lactic acid, making the milk sour. Casein is present in milk chiefly in its alkaline form, and in conjunction with calcium phosphate. Milk absorbs germs from the air and from unclean vessels very readily. Good, clean, uncontaminated milk ought to keep fresh, exposed in a clean room at a temperature of 68 deg. F., for 48 hours without souring. If the milk is tainted in any way it will sour in a few hours. Boiled milk will keep fresh half as long again as fresh milk. Milk absorbs odors very quickly, therefore should never be left in a refrigerator with stale cheese, ham, vegetables, etc., unless in an air-tight jar. It should never be left exposed in a sick room or near waste pipes. Absolute cleanliness is necessary for the preservation of milk; vessels in which it is to be kept must be thoroughly scalded with boiling water, not merely washed out with warm water.
Methods of Preserving Milk.
Milk to be thoroughly sterilized and germ free must be heated to the boiling point (212 deg. F.). This may be done by putting the milk into perfectly clean bottles and placing in a rack, in a kettle of boiling water, remaining until it reaches the necessary degree of heat. The bottle should be closely covered immediately after with absorbent cotton or cotton batting in order to prevent other germs getting into the milk.
The difference between pasteurizing and sterilizing is only in the degree of heat to which the milk is subjected. In pasteurizing, the milk is kept at a temperature of 170 deg. F. from 10 to 20 minutes. This is considered a better method for treating milk which is to be given to young children, as it is more easily digested than sterilized milk. All milk should be sterilized or pasteurized in warm weather, especially for children.
Cheese is one of the most nutritious of foods, and when meat is scarce makes an excellent substitute, as it contains more protein than meat. Cheese is the separated casein of milk, which includes some of the fats and salts.
Eggs contain all the ingredients necessary to support life. Out of an egg the entire structure of the bird—bones, nerves, muscles, viscera, and feathers—is developed. The inner portion of the shell is dissolved to furnish phosphate for the bones. The composition of a hen's egg is about as follows (Church):—
+ + -+ White In Yolk In 100 parts. 100 parts. + + -+ Water 84.8 Water 51.5 Albumen 12.0 Casein and albumen 15.0 Fat, sugar, Oil and fat 30.0 extractives, etc. 2.0 Pigment Mineral matter 1.2 extractives, etc. 2.1 Mineral matter 1.4 + + -+
The albumen—or the "white"—of an egg is greatly altered by cooking. When heated beyond boiling point it becomes a very indigestible substance. Eggs cooked at a temperature of about 170 deg. F., leaving the whites soft, are easily digested. A raw egg is ordinarily digested in 1-1/2 hour, while a baked egg requires from 2 to 3 hours. Eggs baked in puddings, or in any other manner, form one of the most insoluble varieties of albumen.
Gelatin is obtained from bones, ligaments, and other connective tissues. In combinations with other foods it has considerable nutritive value. The place given to it by scientists is to save the albumen of the body; as it does not help to form tissue or repair waste it cannot replace albumen entirely. Gelatin will not sustain life, but when used in the form of soup stock, etc., is considered valuable as a stimulant.
* * * * *
LEGUMES—PEAS, BEANS AND LENTILS.
These vegetables contain as much protein as meat; yet, this being inferior in quality to that contained in meat, they can scarcely be given a place in the same class; therefore we will give them an intermediate position in food value between meat and grains. From the standpoint of economy they occupy a high place in nutritive value, especially for outdoor workers. (See Recipes.)
Fats and Oils.
Fats and oils contain three elements—carbon, oxygen and hydrogen. About one-fifth of the body is composed of fat. Before death results from starvation 90 per cent. of the body fat is consumed.
USES OF FAT.
(1) To furnish energy for the development of heat; (2) to supply force; (3) to serve as covering and protection in the body; (4) to lubricate the various structures of the body; and (5) to spare the tissues. The fats and oils used as food all serve the same purpose, and come before the carbohydrates in fuel and force value; in combination with proteids, they form valuable foods for those engaged in severe muscular exercise, such as army marching, mining expeditions, etc.
Fats and oils are but little changed during digestion. The fat is divided into little globules by the action of the pancreatic juice and other digestive elements, and is absorbed by the system. Fat forms the chief material in adipose tissue, a fatty layer lying beneath the skin, which keeps the warmth in the body, and is re-absorbed into the blood, keeping up heat and activity, and preserving other tissues during abstinence from food. Fat sometimes aids the digestion of starchy foods by preventing them from forming lumpy masses in the mouth and stomach, hence the value of using butter with bread, potatoes, etc. The animal fats are more nutritive than the vegetable, butter and cream heading the list. Cooking fats at a very high temperature, such as frying, causes a reaction or decomposition, which irritates the mucous membrane and interferes with digestion.
The principal animal fats are butter, cream, lard, suet, the fat of mutton, pork, bacon, beef, fish and cod liver oil. The vegetable fats and oils chiefly used as food are derived from seeds, olives, and nuts. The most important fats and oils for household purposes are:
Butter, which contains from 5 to 10 per cent. of water, 11.7 per cent. fat, 0.5 per cent. casein, 0.5 per cent. milk sugar (Konig). The addition of salt to butter prevents fermentation. Butter will not support life when taken alone, but with other foods is highly nutritious and digestible.
Cream is one of the most wholesome and agreeable forms of fat. It is an excellent substitute for cod liver oil in tuberculosis. Ice cream when eaten slowly is very nutritious.
Lard is hog fat, separated by melting.
Suet is beef fat surrounding the kidneys.
Cottolene is a preparation of cotton-seed oil.
Oleomargarine is a preparation of beef fat provided as a substitute for butter.
Olive oil is obtained from the fruit, and is considered to be very wholesome; in some cases being preferred to either cod-liver oil or cream for consumptives.
COTTON SEED OIL.
Cotton seed oil is frequently substituted for olive oil.
Nuts contain a good deal of oil.
The idea of starchy foods is usually connected with such substances as laundry starch, cornstarch, arrow root, etc. These are, of course, more concentrated forms of starch than potatoes, rice, etc. Many starchy foods contain other ingredients, and some are especially rich in proteids.
The following table may help to make this clear (Atwater):—
PERCENTAGE OF STARCH IN VEGETABLE FOODS.
-+ - Per Cent. -+ - Wheat bread 55.5 Wheat flour 75.6 Graham flour 71.8 Rye flour 78.7 Buckwheat flour 77.6 Beans 57.4 Oatmeal 68.1 Cornmeal 71.0 Rice 79.4 Potatoes 21.3 Sweet Potatoes 21.1 Turnips 6.9 Carrots 10.1 Cabbage 6.2 Melons 2.5 Apples 14.3 Pears 16.3 Bananas 23.3 -+ -
It is estimated that starch composes one-half of peas, beans, wheat, oats and rye, three-fourths of corn and rice, one-fifth of potatoes. Vegetable proteids, as already stated, are less easily digested than those belonging to the animal kingdom, therefore it must be remembered that a purely vegetable diet, even though it may be so arranged as to provide the necessary protein, is apt to over-tax the digestive organs more than a mixed diet from both the animal and vegetable kingdoms. Much depends upon the cooking of the starchy foods in order to render them digestible. (Study chapter on Digestion in the Public School Physiology.)
The digestion of starch—which is insoluble in cold water—really begins with the cooking, which by softening the outer coating or fibre of the grains, causes them to swell and burst, thereby preparing them for the chemical change which is caused by the action of the saliva in converting the starch into a species of sugar before it enters the stomach. Substances which are insoluble in cold water cannot be absorbed into the blood, therefore are not of any value as food until they have become changed, and made soluble, which overtaxes the digestive organs and causes trouble. The temperature of the saliva is too low to dissolve the starch fibre unaided. Each of the digestive juices has its own work to do, and the saliva acts directly upon the starchy food; hence the importance of thoroughly masticating such food as bread, potatoes, rice, cereals, etc. The action of heat, in baking, which causes the vapor to rise, and forms the crust of starchy food, produces what is called dextrine, or partially digested starch. Dextrine is soluble in cold water, hence the ease with which crust and toast—when properly made—are digested. It is more important to thoroughly chew starchy food than meat, as it is mixed with another digestive juice, which acts upon it in the stomach.
There are many varieties of sugar in common use, viz.: cane sugar, grape sugar or glucose, and sugar of milk (lactose). As food, sugars have practically the same use as starch; sugar, owing to its solubility, taxes the digestive organs very little. Over-indulgence in sugar, however, tends to cause various disorders of assimilation and nutrition. Sugar is also very fattening, it is a force producer, and can be used with greater safety by those engaged in active muscular work. Cane sugar is the clarified and crystallized juice of the sugar cane. Nearly half the sugar used in the world comes from sugar cane, the other half from beet roots. The latter is not quite so sweet as the cane sugar. Sugar is also made from the sap of the maple tree, but this is considered more of a luxury; consequently, not generally used for cooking purposes.
MOLASSES AND TREACLE.
Molasses and treacle are formed in the process of crystallizing and refining sugar. Treacle is the waste drained from moulds used in refining sugar, and usually contains more or less dirt.
Glucose, or grape sugar, is commonly manufactured from starch. It is found in almost all the sweeter varieties of fruit. It is not so desirable for general use as cane sugar.
Honey is a form of sugar gathered by bees from the nectar of flowering plants, and stored by them in cells. Honey contains water 16.13, fruit sugar 78.74, cane sugar 2.69, nitrogenous matter 1.29, mineral matter 0.12 per cent. (Konig.)
While the grains contain less proteid than the legumes, they are more valuable on account of the variety of the nutrients contained in them, and are more easily adapted to the demands of the appetite. They, however, require long, slow cooking in order to soften the fibre and render the starch more soluble. Among the most important we may place:
A wheat kernel may be subdivided into three layers. The first or outer one contains the bran; second, the gluten, fats and salts; third, the starch. Some of the mineral matter for which wheat is so valuable is contained in the bran, hence the value of at least a portion of that part of the wheat being included in bread flour—not by the addition of coarse bran (which is indigestible) to the ordinary flour, but by the refining process employed in producing whole wheat flour. While wheat is used in other forms, its principal use as food is in the form of flour.
The following table, giving the composition of bread from wheat and maize, will be of interest (Stone):—
COMPOSITION OF BREAD FROM WHEAT AND MAIZE.
-+ In Air-Dry Material. + + -+ -+ -+ + Nitrogen Water. Ash. Fat. Fibre. Protein. free extract. -+ + -+ -+ -+ + P.ct. P.ct. P.ct. P.ct. P.ct. P.ct. Bread from whole winter wheat 3.07 2.33 1.22 2.86 15.70 74.82 Bread from whole spring wheat 7.46 1.69 1.24 2.80 15.26 71.55 Bread from fine flour, winter wheat 10.39 .59 .32 .44 11.94 76.32 Bread from fine flour, spring wheat 8.00 .43 .47 .39 14.41 76.30 Corn bread from whole maize 3.40 1.88 4.14 2.53 12.88 75.17 -+ + -+ -+ -+ +
-+ In Dry Matter + - - Nitrogen Ash. Fat. Fibre. Protein. free extract. - - - P.ct. P.ct. P.ct. P.ct. P.ct. Bread from whole winter wheat 2.40 1.25 2.95 16.20 77.20 Bread from whole spring wheat 1.82 1.34 3.02 16.49 77.33 Bread from fine flour, winter wheat .66 .35 .49 13.33 85.17 Bread from fine flour, spring wheat .47 .51 .42 15.66 82.94 Corn bread from whole maize 1.95 4.29 2.62 13.33 77.81 - - -
The most valuable food product manufactured from flour is bread.
Bread contains so many of the ingredients required to nourish the body, viz.: fat, proteid, salts, sugar and starch, that it may well be termed the "staff of life." As it does not contain enough fat for a perfect food the addition of butter to it renders it more valuable as an article of diet. Mrs. Ellen H. Richards gives the following explanation of what constitutes ideal bread: "(1) It should retain as much as possible of the nutritive principles of the grain from which it is made; (2) it should be prepared in such a manner as to secure the complete assimilation of these nutritive principles; (3) it should be light and porous, so as to allow the digestive juices to penetrate it quickly and thoroughly; (4) it should be nearly or quite free from coarse bran, which causes too rapid muscular action to allow of complete digestion. This effect is also produced when the bread is sour." Bread is made from a combination of flour, liquid (either milk or water), and a vegetable ferment called yeast (see yeast recipes). The yeast acts slowly or rapidly according to the temperature to which it is exposed. The starch has to be changed by the ferment called diastase (diastase is a vegetable ferment which converts starchy foods into a soluble material called maltose) into sugar, and the sugar into alcohol and carbonic acid gas (carbon dioxide), when it makes itself known by the bubbles which appear and the gradual swelling of the whole mass. It is the effect of the carbonic acid gas upon the gluten, which, when checked at the proper time before the ferment becomes acetic (sour) by baking, produces the sweet, wholesome bread which is the pride of all good housekeepers. The kneading of bread is to break up the gas bubbles into small portions in order that there may be no large holes and the fermentation be equal throughout. The loaf is baked in order to kill the ferment, to render the starch soluble, to expand the carbonic acid gas and drive off the alcohol, to stiffen the gluten and to form a crust which shall have a pleasant flavor. Much of the indigestibility of bread is owing to the imperfect baking; unless the interior of the loaf has reached the sterilizing point, 212 deg. F., the bacteria contained in the yeast will not be killed, and some of the gas will remain in the centre of the loaf. The scientific method of baking bread is to fix the air cells as quickly as possible at first. This can be done better by baking the bread in small loaves in separate pans, thereby securing a uniform heat and more crust, which is considered to be the most easily digested part of the bread. Some cooks consider that long, slow baking produces a more desirable flavor and renders bread more digestible. One hundred pounds of flour will make an average of one hundred and thirty-five pounds of bread. This increase of weight is due to the addition of water.
Macaroni is a flour preparation of great food value. It contains about six per cent. more gluten than bread, and is regarded by Sir Henry Thompson as equal to meat for flesh-forming purposes. Dieticians say that macaroni, spaghetti and vermicelli are not used so extensively as their value deserves.
Buckwheat is the least important of the cereals.
Rye is almost equal to wheat in nutritive value. Its treatment in regard to bread making is similar to that of wheat.
Corn contains fat, proteid and starch, and produces heat and energy. It is very fattening, and when eaten as a vegetable is considered difficult of digestion. Cornmeal is a wholesome food; it contains more fat than wheat flour, and less mineral matter.
Rice constitutes a staple food of a great many of the world's inhabitants. It contains more starch than any other cereal, but when properly cooked is very easily digested. It should be combined with some animal food, as it contains too little nitrogen to satisfy the demands of the system. It forms a wholesome combination with fruit, such as apples, peaches, prunes, berries, etc.
Barley is almost equal to wheat in nutritive value. It contains more fat, mineral matter and cellulose (cellulose is often called indigestible fibre, as it resists the solvent action of the digestive juices, and is of no value as a nutrient), and less proteid and digestible carbohydrates.
Oatmeal is one of the most valuable foods. Oats contain fat, proteid, salts and cellulose, in addition to a large percentage of starch. The nutritive value of oatmeal is great, but much depends upon the manner of cooking. (See recipes.) People who eat much oatmeal should lead a vigorous outdoor life. The following analysis of oatmeal is given (Letheby):—
Nitrogenous matter 12.6 per cent. Carbohydrates, starch, etc. 63.8 " Fatty matter 5.6 " Mineral matter 3.0 " Water 15.0 " —— Total 100.0
Legumes—peas, beans and lentils—have an exceedingly leathery envelope when old; and unless soaked for a long time in cold water—in order to soften the woody fibre—and are then cooked slowly for some hours, are very indigestible. Pea and bean soups are considered very nutritious. Lentils grow in France; they are dried and split, in which form they are used in soups.
Potatoes are the most popular of all the tubers. As an article of diet they possess little nutritive value, being about three-fourths water. They contain some mineral matter, hence the reason why they are better boiled and baked in their skins, so as to prevent the escape of the salts into the water. Potatoes are more easily digested when baked than cooked in any other form.
Beets contain between 85 and 90 per cent. of starch and sugar, some salts, and a little over one per cent. of proteid matter. Young beets, either in the form of a vegetable or a salad, are considered to be very wholesome.
CARROTS, TURNIPS, PARSNIPS, OYSTER PLANT.
Carrots, turnips, parsnips and oyster plant, although containing a large percentage of water, are considered valuable as nutrients, the turnip being the least nutritious.
Green vegetables do not contain much nutriment, and are chiefly valuable as affording a pleasing variety in diet; also for supplying mineral matter and some acids. In this class we may include cabbage, cauliflower, spinach, lettuce and celery.
Tomatoes are wholesome vegetables; on account of the oxalic acid they contain they do not always agree with people of delicate digestion.
Cucumbers are neither wholesome nor digestible.
Asparagus is a much prized vegetable. The substance called asparagin which it contains is supposed to possess some value.
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.
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-scorbutics; (5) as laxatives and cathartics; (6) to stimulate the appetite, 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 contain proteid, with some starch and sugar, but are not considered valuable as nutrients. Cocoanuts, almonds and English walnuts are the most nutritious.
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 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 Albuminoids 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 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 analysis 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
The use of alcohol is wholly unnecessary for the health of the human organism. (See Public School Physiology and Temperance.)
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.
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 circumstances 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 (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 is considered to be the cheapest fuel.
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 space 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. When the wood is thoroughly kindled and the first layer of coal heated, fill the fire-box with coal even with the top of the oven. When the blue flame becomes white, close the oven damper, and when the coal is burning freely, shut the direct draft. When coal becomes bright red all through it has lost most of its heat. A great deal of coal is wasted by filling the fire-box too full and leaving the drafts open till the coal is red. To keep a steady fire it is better to add a little coal often rather than to add a large quantity and allow it to burn out. Never allow dust or cinders to accumulate around a range, either inside or out. Learn to open and shut the oven door quietly and quickly. Study the amount of fire required to heat the oven to the desired temperature. Learn which is the hotter or cooler side of the oven, and move the article which is being baked as required, being very careful to move it gently.