How does heat affect the coagulation of eggs?

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Procedure:

1. Scald milk in double boiler.
2. Beat egg slightly (white and yolk should be thoroughly mixed but not foamy.)
3. Stir sugar and salt gradually into egg.
4. Pour scalded milk into egg-sugar mixture, stirring constantly.
5. Add 1/4 tsp. vanilla and stir.

Pour the mixture into two custard cups and cook according to the directions given below for the appropriate treatment. Each formulation makes 2 custards. Your TA will help members of your group decide which treatments to make. Each group should make all treatments.

Preparation of custards.

1. Oven Control
   1. Preheat oven to 350°F.
   2. Prepare custard mixture as directed above.
   3. Set custard cup in a Pyrex baker as deep as the custard cup.
   4. Fill the baker with hot water to the level of the custard in the cup. Place in oven.
   5. Bake until the tip of a sharp knife inserted halfway between the center and edge of the custard comes out clean. (Approx. 40-50 min.)
   6. Remove immediately from hot water and place on a rack to cool, then evaluate custard.
2. Oven Variation:

   Into a 350°F oven as in the Oven Control but without doing Step 4. Remove when a knife inserted into the custard comes out clean. Record the baking time.

3. 2 Egg Variation: (bake in an oven as in Oven Control.)

   Prepare custard according to the basic mixture, using 96 g of whole egg (2 eggs).

4. Microwave

   Cover the custard cup with plastic wrap. Poke a few holes in the plastic to allow steam to escape. Adjust microwave time and power to get the best product you can.