Evaluation of physical quality and chemical composition of commercially available table eggs

Abstract

A variety of commercial table eggs are available in retail outlets, but little information is available on their physical quality and chemical composition. In this study, 49 eggs were analysed, divided into three types (conventional, organic and omega-3 rich) and three grades (A, B and C). The quality of the eggs was assessed on the basis of physical structure and chemical composition. No significant (p>0.05) differences were found in egg weight, shell weight, yolk height, albumen height, shell thickness, shape index and Haugh unit between egg types, regardless of grade. Similarly, no significant (p>0.05) differences were found between grades A and B for most parameters except shell weight. In the traditional eggs, grade A had a higher (p<0.05) egg weight and albumen height than grades B and C. For organic eggs, grade A showed significantly (p>0.05) higher egg weight, yolk index, yolk height and Haugh unit than grade B. In the omega-3 rich eggs, grade A had greater (p<0.05) egg weight, albumen height, and yolk height, while grade B had a higher Haugh unit than grade A. No significant (p>0.05) differences were found between the egg types in dry matter, protein and fat contents of the albumen and yolk. However, ash content of the yolk was significantly (p<0.05) higher in organic eggs (2.4%) compared to omega-3 rich (2.1%) and conventional eggs (1.8%). In conclusion, while most physical traits did not vary significantly across egg types and grades, notable differences in yolk ash content suggest variations in mineral composition. These findings are relevant to consumers seeking nutrient-dense options and to producers aiming to enhance egg quality and market value.