30 BULLETIN 123, U. S. DEPARTMENT OF AGRICULTURE. 
Baked (3): Bake in dish, skin having been removed first; glaze occasionally 
with butter or meat fat. 
Boiled: Cook one in skin, another without skin. 
Steamed: Cook one in skin, another without skin. 
Mashed: Boil one potato, mash, season with butter, salt, etc., add hot milk, 
measured, and note how much the potato will absorb. 
Cut and boiled: Cut a potato in slices or cubes, add milk and seasoning as 
in previous recipe, and compare results. Add grated cheese to part. 
Soup: Make soup from mashed potato in same fashion as with onion in 
previous lesson. Note lack of flavor—some addition of onion or celery indicated. 
Also note slight thickening needed in potato soup compared with onion soup. 
Salad: Make salad with cooked potato and onion like apple and onion salad 
in Lesson IV. 
Look up composition of potato. Does this suggest what other materials should 
be added? 
For other dishes in which potatoes are an important ingredient, refer to 
standard cookbooks. 
Comparison of rice and potato: Weigh out one-half pound rice, wash and 
cook in 2 quarts of rapidly boiling salted water until tender, and drain. The 
water may be reserved for soup in next lesson. Cook an equal money value 
of potatoes. Compare value of results, including cost of fuel and labor ex- 
pended and considering refuse in potatoes, ete. 
EXPERIMENTS WITH STARCHY MATERIALS. 
Let each student or each two take a different form of starchy substance, 
tapioca (flaked, pearl, or granulated), cornstarch, rice flour, sago, starch from 
potato, ete.; cook with water until fairly transparent, salt slightly, and taste 
of each to learn to recognize characteristic flavor. Take equal amounts of each 
of them, add to each the same amount of fruit juice and sugar, and taste again 
to see how the flavor of the fruit affects or disguises the characteristics of each 
kind of starch. Note possibility of substitutions in recipes. Samples of these 
starches may be treated with dilute iodin before and after cooking. Dilute iodin 
turns starch a blue color. (See Lesson I, p. 8.) 
REVIEW QUESTIONS, LESSON V. 
1. Show differences between bulbs and roots; roots and tubers. 
2. What are the principal food substances derived from roots? 
3. Where did the potato originate and when was it introduced into Europe? 
4, What differences in the nature of the new and old potato? How do these 
influence methods of cooking each? 
5. What is the weight of an average potato? 
6. How many pounds of potatoes are probably consumed in your household 
in a week or month? 
7. How may you find that the potato contains starch? 
8. How should potatoes as ordinarily purchased be selected for baking, 
steaming, croquettes, etc.? 
9. Describe general preparation and use of the sweet potato. 
10. What other roots and tubers furnish valuable starch? 
LESSON VI. SUCCULENT ROOTS. 
In the majority of these root vegetables the main or taproot has 
become thick and fleshy. If cross sections of such roots are care- 
fully examined, with or without a microscope, it will aid one to 
