Eggs are non expensive but nutritious food. It is one of the main sources of protein, amino acid and fatty acids. Conventional production of family system supply about 10% market demand of table eggs in most developing countries. Egg productions sustain the small families economy and generate sustainable income. One of the constraints to increased production of egg in Nigeria is to preserve the egg qualities by selecting the most proper storage system. Several physio-chemical modification occurs inside an egg during storage period. Easily observable physical change include, thinning of the thick albumen. The change is related to the ageing of the yolk and the albumen and flattering of the yolk, (Stadelman et al., 1995).

Another well known quality parameter is the yolk index. The albumen that surrounds the yolk which is called the thick albumen progressively liquefies and thins with time, transforming itself into thin albumen. This phenomenon is caused by deterioration of the gelatinous structure of the albumen, that is due to changes in the complex lysozine ovomucine caused by increase of PH during the storage period. (Cotterill and winter 1995)

Another obvious changes that can be observed during egg ageing is flattening of the yolk caused by weakening of the vitelline membrane (Tumova et al., 1993). These changes are used for the determination of the quality indices of the eggs. The Haugh unit with an index based on the thickness of the egg is adopted by the European community to select eggs.

Proper storage of eggs is essential to preserve the quality and cooking characteristics. Improper storage condition can reduce the grade of eggs within a few days. The principle degrading factors are high temperature and dehydration. Improper storage has been reported to produce some observed changes, enlargement of the air cell, absorption of odors and off flavors if stored near pungent foods (Young, 1997). The knowledge of effect of temperature degree on the quality control of internal composition of eggs is essential to make comparison between eggs stored at room temperature, air tight box and refrigerator. 

Egg value is determined by standard based on interior and exterior characteristics of individual eggs to reflect both quality and size of the eggs. High quality egg contents are indicated by firm, thick albumen and yolks. The air cell is very small (less than 4.7mm in depth). The value of each egg is determined individually by the lowest exterior or interior quality factors. Most downgrading egg shell are due to external shell factors, but have high quality egg contents. The parameters used to monitor egg quality include, egg weight loss, shape index, yolk index ,albumen height, Haugh unit and shell thickness.
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