CHEMICAL CHARACTERISTICS OF WHOLE EGGS FROM AVIAN SPECIES: A COMPARATIVE STUDY

Abstract

Egg weight and egg component, chemical composition, fatty acids and cholesterol, amino acids and minerals content in conventional eggs (ostrich, duck, hen and quail) were studied. Results indicated that, the ostrich egg had highest egg weight (g), and so had highest percent of weight and shell, while duck eggs showed highest percent of yolk. For chemical composition, Ostrich egg have had more highest moisture, carbohydrates and cholesterol contents, while highest values of protein, lipid and total ash were obtained by duck egg (at wet weight basis). Oleic, palmitic, linoleic, stearic and palmitoleic acids were the major fatty acids in egg yolk of all studied eggs. The hen egg had highest oleic and stearic acid, while duck egg had highest palmitic acid. The highest linoleic acid was obtained by quail egg and the highest palmitoleic acid was found by ostrich egg. Concerning amino acids content, glutamic acid had the highest one in the protein composition followed by aspartic acid and leucine in all studied eggs. The highest values of aspartic and leucine were obtained by hen eggs, while the highest values of glutamic acid were obtained by ostrich egg. Concerning minerals content, the ostrich egg had the highest values of iron content. The duck egg had highest values of sodium, potassium and zinc content, while the highest values of magnesium and phosphorus were obtained by hen eggs. Finally the highest calcium content was obtained by quail eggs.