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Experiment 17

A. To determine the effect of different methods of cooking on the color of green vegetables.

Use 1/8 pound (56 grams) of spinach, lettuce, Brussels sprouts, green beans cut in 1-inch strips, or green asparagus. Use 1 cup of water. Cook 10 to 25 minutes, the time depending upon the vegetable used, but decide upon the length of time the vegetable is to be cooked before experiments are started. Save the water left from each experiment to compare for color and flavor. Notice the texture of the vegetable.

1. Pour boiling water over the vegetable. Cook covered for the length of time agreed upon.

2. Repeat A1, but cook uncovered.

3. Add salt to the cooking water. Use 1/4 teaspoon per cup of water. Cook uncovered and start in boiling water.

4. Cook uncovered in boiling distilled water.

5. Cook uncovered in boiling distilled water to which 1/16 teaspoon of soda has been added.

6. Cook uncovered in boiling distilled water to which Y\ teaspoon of vinegar has been added.

7. Cook in a steamer.

8. Cook in a pressure cooker, 10 minutes at 15 pounds pressure.

9. Cook in milk.

If desired, some of the cooking water may be tested for iron and phosphates.

In which case is the green color of the vegetable best preserved? Is there any difference in the texture of the vegetables with soda and with vinegar added?

Vegetable used:

Time of cooking

Color of vegetable

Texture

Color and amount of water

Flavor

Results and conclusions.

B. To determine the effect of different methods of cooking on the color of red vegetables.

Use red cabbage if it can be obtained. If it is not obtainable, use red onions or beets. Repeat the directions under A for cooking. Vegetable used:

C. To compare the effect of different methods of cooking on the color of yellow vegetables.

Use carrots or squash. Repeat the directions under A for cooking. Do not confuse caramelization of sugar by alkali with pigment change of color.

Vegetable used:

Compare the effect of acid and alkali on the green, red and yellow pigments found in vegetables. What is the effect of the soda on the texture? Of the vinegar? Which is the preferable way of cooking each of the different colored vegetables ?

Experiment 18

To determine the effect of alkaline and neutral water upon the color of white cereals and vegetables.

la. To 1 1/3 cups of boiling water add 1/4 cup of washed rice. Cook until tender. Add more boiling water if necessary during cooking. Remove about 1/2 of the cooked rice from the sauce pan and drain.

lb. To the rice remaining in the sauce pan from \a, add 1/8 to 1/16 of a teaspoon of cream of tartar. Cook 2 minutes and drain.