Cooking Of Protein

Of all the proteins, "Albumin," of which there are many varieties, is the most important and needs most care in the cooking to make it easily digested.

The majority of albumins are soluble in cold water and vegetable acids; they are coagulated by heat, mineral acids and alcohol. The cooking of albumin should be governed by these facts.

"As the white of the egg is nearly pure albumin it will serve as an excellent illustration for demonstrating the effect of heat on the principal constituent of albuminous foods".

Effect Of Temperature Or Test For Cooking Albumin

Into a test tube put some white of egg, place in a sauce pan of cold water, heat gradually, and observe all changes.

1. Raw white of egg is a sticky, clear, pale straw-colored liquid, and readily digested.

2. When water reaches the temperature 134° F. white streaks will be seen in a semi-solid white substance which is found to be readily digested.

3. When water reaches the temperature 160° F. the egg will be firm, soft, and jelly-like, and is readily digested.

4. When water reaches 212° F. the egg will be tough white jelly and less readily digested.

5. When egg is heated to 300° P. or higher (for example put the test tube directly over flame), the egg will almost immediately become hard and tenacious.

These albumin tests demonstrate that albuminous foods are most tender and readily digested when cooked at a low temperature but when coagulated at too high a temperature are tough and indigestible.

Reheated albuminous foods are less digestible than freshly cooked because the albumin is much hardened by the second cooking. The principal foods requiring care in preparation because of the albumin are eggs, meat, and fish. These will be considered further under their separate headings.