Experiment 58

To determine the conditions most favorable for the clotting of milk by rennin.

1. Use 1/2 cup of raw milk warmed to 35° to 40°C. Add 1/4 of a junket tablet that has been powdered and 1/2 tablespoon of sugar. Stir to dissolve. Put the junket mixture into a glass container or a Pyrex baking cup. Let stand at room temperature. Keep a record of the time required for setting. Determine when it is set by tipping the container slightly to one side.

2. Repeat 1, but use pasteurized milk.

3. Repeat 1, but set in the refrigerator after adding the junket.

4. Repeat 1, but dissolve the junket in 1 tablespoon of water. Boil, concentrating the water to 1 teaspoon. Add to the milk and sugar.

5. Repeat 1, but boil the milk, then cool to 35° to 40°C. before adding the junket.

6. Repeat 1, but dilute the milk with water, using 1/4 cup water and 1/4 cup of milk.

7. Repeat 6, but use cereal water instead of water for diluting the milk. The cereal water should be a little thinner than the consistency of a medium white sauce.

8. Repeat 1, but add 1/16 teaspoon of soda to the milk.

9. Repeat 8, but increase the soda to 1/4 teaspoon.

10. Repeat 1, but double the amount of sugar using 1 tablespoon (12.5 grams).

11. Add 1 tablespoon of grated raw pineapple juice to 1/2 cup of milk. Add the sugar but not the junket.

Which ones set? Which do not set? Explain. Compare the firmness of the clot formed in the various experiments.



Texture of clot


Results and conclusions. .