WHY EGGS CHANGE

Evening Star, Issue 21965, 27 February 1935, Page 12

WHY EGGS CHANGE

A SELF-DIGESTIVE PROCESS An egg deteriorates in storage because it is digesting itself. Recent work by food chemists of the United States Department of Agriculture shows that trypsin, one of - the enzymes present in the pancreatio juice of the human body, is present in egg white, and is quite probably responsible for the changes that occur in eggs-when they are stored for several months. The function of trypsin in the human body is to digest protein foods. Presumably that is just what it does in the egg white. For years scientists have suspected that trypsin or some other proteolytic enzyme was responsible for two of the important changes that take place under storage—a weakening of the membrane around the yolk, causing it to break more easily, and an increase m the amount of thin white; The search of trypsin in egg white wae complicated by the presence of a substance in'tile thin white which inhibits any further action of the enzyme. As a result, tests of mixed thick and thin egg white have failed to show the presence of trypsin. The department chemists next separated the thin and thick white and tested each. They found trypsin then in the thick white without any difficulty. As a check on, their conclusions the investigators took a fresh egg, punched « small hole in the end, and injected trypsin into the thick white with a hypodermic needle. Fresh eggs so treated took on in a few hours the characteristic of eggs held in storage for many months. The whites became thin and watery, and the yolks became fragile. _ Within two days it was almost impossible to break the egg without breaking the yoJk. This diagnosis of one of the contributing causes of the changes that take place in storage eggs provides a starting point for further research. Now that the cause is known the next step is to try to find s remedy which may be put into application commercially, ■