Woodruff, S., and Nicoli, L. Starch Gels. Cereal Chem. 8: 243 (1931).

Woodruff, S., and Webber, L. R. A Photomicrographic Study of Gelatinized Wheat Starch. J. Agri. Research 46: 1099 (1933).

Working, E. B. Lipoids, a Factor Influencing Gluten Quality. Cereal Chem. 1: 153 (1924).

Working, E. B. Some Oxidizing Effects of Flour Bleaching. Cereal Chem. 5: 431 (1928).

Whymper, R. Colloid Problems in Bread Baking. Third Report on Colloid Chemistry. British Assoc, for the Advancement of Science, p. 61 (1920).

Experiment 71

To see if gluten can be washed from a batter.

To 1/2 cup of flour add slowly while mixing 1/2 cup of water. Mix until smooth and free from lumps; then beat for 1 minute. Let stand 10 minutes. Place in a fine sieve. Wash in a stream of water and try to collect the gluten. What happens?

Experiment 72

A. To wash gluten from a dough.

1. To 1/2 cup of bread flour (56 grams) add 1/6 cup of water (40 cc). Stir 40 times; then knead 80 times. Let stand 10 minutes. Wash under a stream of water to free the gluten of starch. Wash until the water is clear. The product obtained is gluten. What is its weight? What are its characteristics? If desired the gluten balls may be baked and their comparative baked volumes obtained. Bake at 200° to 210°C. (390° to 410°F.).

2. Repeat A1, but use pastry flour. Compare the resulting gluten and its quantity with that from bread flour. Bake.

B. To determine the effect of substituting milk for the water and adding baking powders to the flour.

1. Repeat Al, but substitute milk for the water.

2. Repeat Al, but substitute sour milk for the water.

3. Repeat A1, but sift 1/2 teaspoon of tartrate baking powder with the flour before adding the water.

4. Repeat B3, but use a phosphate baking powder.

5. Repeat B3, but use sulfate-phosphate baking powder.

6. Add different proportions of sugar to the flour and try to wash out the gluten. The amount of sugar added can be based on the proportion of sugar to flour used in muffins and different cake recipes.

Experiment 73

To determine the best proportion of water to use with the kind or grade of flour that is to be used in making bread.

Brand of flour used:

Recipe:

Ingredients

Approximate measure

Large dough or large loaf, grams

Small dough or small loaf, grams

Flour.............

3 1/8 cups

350.0

100.0

Yeast.............

3/4 cake

10.5

3.0

Sugar.............

3/4 tablespoon

10.5

3.0

Salt...............

1 1/4 teaspoons

5.25

1.0

Fat...............

1/2 tablespoon

6.5

0.0

Fermentation

First punch 105 minutes (28-30°C.)

Second punch 50 minutes

Pan 25 minutes after second punch

Proof 55 minutes

Bake 35 minutes (220°C.)

Use the large or small dough for baking. The fermentation time for the large dough or large loaf is 265 minutes or nearly 4 1/2 hours. That for the small dough or small loaf is 290 minutes or nearly 5 hours. If a shorter fermentation period is desired increase the amount of yeast used as suggested in Table 47 and decrease the fermentation time for punches and panning accordingly.

Determine the temperature of the water necessary to bring the dough to 28°C. This may be done for the first trial by taking the temperature of the room plus the temperature of the flour and substracting from 84. The result will be the temperature of water to use, to bring the dough out at 28°C. This will not always bring the temperature of the dough out at 28°C, especially if the temperature of the room is rather low and mixing is continued for some time. To find the temperature of the water to bring the dough out at 30°C, subtract the temperature of the room plus the temperature of the flour from 90.

Sift the flour. Dissolve the sugar and salt in a portion of the water and mix the yeast in another part. Add water and melted fat to the flour and mix to a smooth dough. If a bread mixer is used, mix until the dough is smooth. Keep a record of the time and mix other batches of dough for the same length of time. If mixed with a spoon mix until a dough is formed, then knead on a flat surface until smooth. The length of time for kneading depends upon the vigor and rapidity of kneading. It is better to work out a definite method of kneading and count the punches used. Otherwise the amount of kneading will produce variations and it will then be difficult to determine variations due to other causes. Try 300 punches, unless it is found that, owing to method of kneading or other factors, more or less kneading gives better results.

For fermentation place in a container of suitable size and cover. To obtain a constant temperature in a cooking laboratory the dough may be placed in a covered bowl or pan and set in a dishpan of water, the water being at the desired temperature for fermentation. Add hot water as needed to keep the temperature constant. The dishpan should be covered to avoid drafts over the top of the bread.

An empty refrigerator makes an ideal proofing cabinet, as it is easy to regulate the temperature by a pan of hot water in the bottom, and it is moist so that there is no tendency for the crust to dry. A china closet, a box, or an oven can also be used.

Leave the dough in the container for the punches and punch just sufficiently to bring the dough to the original volume. Count the strokes used for punching and use the same for all the doughs and the same method of making strokes. For panning, turn out on a smooth surface and knead or fold gently into the desired shape. Use no flour to mold as this flour will not be fermented for the same length of time as that in the dough and may leave streaks in the bread.

Prevent a crust from forming while rising and while in the pan. If necessary, moisten the top occasionally with water.

1. Use 55 per cent of water or 192.5 cc.

2. Use 57.5 per cent of water or 201.2 cc.

3. Use 60 per cent of water or 210 cc.

4. Use 62.5 per cent of water or 218.7 cc.

5. Use 65.0 per cent of water or 227.5 cc.

If preferred a score card may be used instead of the following headings for keeping a record of results of the bread experiments. Write a summary of conclusions of experiments giving applications to cooking.

Volume

Crust appearance

Color

Smoothness

Break and shred

Thickness

Crumb, color

Size of cells

Thinness of cell walls

Elasticity or spring

Tenderness

Odor

Flavor

Results and conclusions.

Experiment 74

To determine the effect of manipulation of the dough upon the volume, the texture, and the tenderness of bread.

A. The extent of mixing and the pressure used in kneading.

1. Use the proportion of water found best under Experiment 73. If this has not been determined, try 60 per cent. Follow directions for mixing given under Experiment 73. Mix 3 times the recipe used. Knead as in Experiment 73, using 400 punches. Weigh the dough and divide into 3 portions. Put part one in the proofing cabinet to rise. Use the remainder of the dough for 2 and 3.

2. Continue kneading one part of the dough from 74,1, for 15 to 20 minutes or use 1000 punches. For the rest of the operations duplicate the procedure under 1.

3. Put the third portion of the dough from 74,1, to rise. When punching after the first fermentation period use more strokes for punching and more pressure. Knead hard just before molding the loaf to put in the baking pan.

B. Method of molding.

Repeat A1, using the regular recipe. When molding the dough for the baking pan pat gently into a long narrow strip that can be rolled for the loaf. Roll around about 2 times and shape and place in pan.

Compare the appearance, volume, texture, and tenderness of the loaves of bread. Compare the shape and direction of cells in the baked loaves. Does rolling compress a part of the dough so that some cells are more compressed than others?

Experiment 75

To determine the effect of fermentation on the volume, the texture, and the tenderness of bread.

Mix 2 times the recipe used. Follow directions given under Experiment 73, using the proportion of water that gave the best loaf. If this has not been determined use 60 per cent. After kneading, weigh and then divide into 2 parts. Mold and shape one loaf and place directly in the baking pan. Let rise to the desired height and then bake. The second half of the dough should be fermented and punched in the regular way before molding and baking. Compare the two loaves for volume, appearance, color of crumb, texture, and tenderness.

Experiment 76

To determine the effect of changing the proportion of ingredients. Mix in the usual way, ferment, and bake the usual time.

A. Salt.

1. Repeat Experiment 73, using the best proportion of water for a control loaf.

2. Increase the salt to 8 grams.

3. Decrease the salt to 2.6 grams.

B. Sugar.

1. Double the sugar in the recipe. Use A1 for a control.

2. Omit the sugar in the recipe.

C. Fat.

1. Double the fat in the recipe. Use A1 for a control.

2. Treble the fat in the recipe.

Compare the effect on volume, appearance, texture, and tenderness of bread of changing the proportion of ingredients.