In order fully to prove or demonstrate one of the very
important effects of heat on food, three petri dishes of
sterilized nutrient jelly, such as is used in bacteriological
studies, may be used if convenient. The jelly in one
dish should be touched with the exposed surface of at
least three of the uncooked foods — preferably one from
each class ^animal foods, fruits, vegetables. The jelly in
a second dish should be touched with the freshly cut
surface of each of the foods previously used. To the
jelly in the third dish a bit of the same foods, freshly
cooked, should be applied.
The dishes must be covered immediately, labeled, and
allowed to stand for a few days before they are examined.
TOPICS FOR STUDY OR DISCUSSION
1. The approximate temperature of the cooking proc-
esses used in this lesson.
2. Other methods of applying heat to food, their ad-
vantages, etc.
3. Fuels used in cooking, their comparative cost,
cleanliness, and ease of regulation or control.
4. Definition of Food.
5. Classification of foods into Protein, Fats, Carbo-
6 PRINCIPLES OF FOOD PREPARATION
hydrates. Water, Minerals. Function, broadly speak-
ing, of each in the diet.
QUESTIONS
1. Name the general effects of heat on food which
are common in the case of both animal and vegetable
foods.
2. What are the effects of heat which are opposite in
the two cases?
3. How does the effect of dry heat differ from that of
moist?
4. How does the effect of high temperature differ
from that of low?
5. Why do potatoes take longer to bake than to boil,
though the temperature of the oven is higher than that
of boiling water?
6. How is it that you can hold your hand in a hot oven
for a few seconds, without being burned, and you can-
not hold it in boiling water?
7. In the case of the meat balls, what physical changes
were brought about by pan-broiling that were not pro-
duced by steaming?
8. Name the protein foods in today's lesson, the car-
bohydrates. What fats were present?
9. Discuss how a meal, planned on the basis of three
of the foods used in class today, could be cooked with
the greatest economy of time and labor, consistent
with the development of the most delicious flavor.
What would be the cost of such a meal for four persons?
(See charts. Appendix A.)
References
Bailey. Sanitary and Applied Chemistry, Chap. II.
Jordan. The- Principles of Human Nutrition, Chap. XVI.
Hutchison. Food and Dietetics, Chap. XXH.
Snyder. Human Foods, Chap. H.
White. The Fuels of the Household.
Encyclopaedia articles on fuels, etc.
CHAPTER II
EFFECT OF SALT ON CELLULOSE
STUDY OF POTATO, A TYPICAL STARCHY VEGETABLE
To the Student. The work in this and in most of the
succeeding chapters will probably occupy at least two
lesson periods. The Corroborative Experiment outlined
at the close of the practical work in cooking pota-
toes will throw light on much that you will observe in
making the various dishes. These experiments can be
omitted where the results are evident from the work
done, but when not actually performed they may be
profitably read over or studied.
Page 6
Presented as published in 1914. Historical recipes may not meet modern food-safety standards. Cook from the modern interpretation, not the original instructions.
AI-modernized reading of the original text
In order fully to prove or demonstrate one of the very important effects of heat on food, three petri dishes of sterilized nutrient jelly, such as is used in bacteriological studies, may be used if convenient. The jelly in one dish should be touched with the exposed surface of at least three of the uncooked foods — preferably one from each class ^animal foods, fruits, vegetables. The jelly in a second dish should be touched with the freshly cut surface of each of the foods previously used. To the jelly in the third dish a bit of the same foods, freshly cooked, should be applied.
The dishes must be covered immediately, labeled, and allowed to stand for a few days before they are examined.
1. The approximate temperature of the cooking processes used in this lesson.
2. Other methods of applying heat to food, their advantages, etc.
3. Fuels used in cooking, their comparative cost, cleanliness, and ease of regulation or control.
4. Definition of Food.
5. Classification of foods into Protein, Fats, Carbo-
hydrates. Water, Minerals. Function, broadly speaking, of each in the diet.
1. Name the general effects of heat on food which are common in the case of both animal and vegetable foods.
2. What are the effects of heat which are opposite in the two cases?
3. How does the effect of dry heat differ from that of moist?
4. How does the effect of high temperature differ from that of low?
5. Why do potatoes take longer to bake than to boil, though the temperature of the oven is higher than that of boiling water?
6. How is it that you can hold your hand in a hot oven for a few seconds, without being burned, and you cannot hold it in boiling water?
7. In the case of the meat balls, what physical changes were brought about by pan-broiling that were not produced by steaming?
8. Name the protein foods in today's lesson, the carbohydrates. What fats were present?
9. Discuss how a meal, planned on the basis of three of the foods used in class today, could be cooked with the greatest economy of time and labor, consistent with the development of the most delicious flavor. What would be the cost of such a meal for four persons? (See charts. Appendix A.)
References
Bailey. Sanitary and Applied Chemistry, Chap. II. Jordan. The- Principles of Human Nutrition, Chap. XVI. Hutchison. Food and Dietetics, Chap. XXH. Snyder. Human Foods, Chap. H. White. The Fuels of the Household. Encyclopaedia articles on fuels, etc.
CHAPTER II
EFFECT OF SALT ON CELLULOSE
STUDY OF POTATO, A TYPICAL STARCHY VEGETABLE
To the Student. The work in this and in most of the succeeding chapters will probably occupy at least two lesson periods. The Corroborative Experiment outlined at the close of the practical work in cooking potatoes will throw light on much that you will observe in making the various dishes. These experiments can be omitted where the results are evident from the work done, but when not actually performed they may be profitably read over or studied.