HCM 238 INTRODUCTION TO FOOD & BEVERAGE PRODUCTION II 694.Fried Eggs/bacon 5.Poached eggs 6.Scott egg 7.Omelets. 3.3.1Effect of Heat on Eggs When eggs are heated, Ovalbumin in the egg white starts to coagulate at 600C (140F) until the whole white is solid and opaque. The proteins of the egg yolk start to coagulate at 700C (1580F) and continue until the yolk is dry and hard. If overcooked, the protein becomes tough and difficult to digest Tull (1990). If an egg is boiled for some time, a green black ring of iron sulphide forms around the yolk. This is due to the reaction of sulphur in the egg white with iron in the egg yolk, particularly in eggs which are not very fresh. This reaction can be prevented to a certain extent by cooling the egg rapidly as soon as it has been cooked. If eggs are heated too quickly, the proteins will coagulate and shrink rapidly, causing any liquid that the egg contains to be squeezed out and the protein to become tough. This is called “Syneresis”. The higher the temperature and the longer the time of cooking, the tougher and more solid the eggs become and, therefore, more difficult to digest thus; fried eggs are harder to digest than poached or scrambled eggs and hard-boiled eggs more difficult to digest than lightly boiled ones (Hildreth, 1977). 3.2.2The Don’ts in Egg Cookery1)Do not wash an egg until you are ready to use it 2)Do not rush egg cooking as they turn tough. 3)Do not use or cook eggs that are just taken from the refrigerators. Very cold eggs cracks when plunged into boiling water to cook. This can be prevented by blanching or making a hole around the egg before placing it in water for boiling. You will find it easier for boiled eggs if you plunge them into cold water just after cooking. 4)Do not differentiate from white and brown coloured egg because colour makes no difference. 5)Do not beat egg while in an aluminum container as it will turn dark. Do not dispense powdered eggs as they are just as good as fresh ones. 6)Do not let egg stand in a temperature of about 650C and above.