Albumen Quality of Fresh and Stored Table Eggs: Hen Genotype as a Further Chance for Consumer Choice

SIMPLE SUMMARY: Consumer interest in food products and their origins is increasing. Knowledge of egg production and quality of purebred hens during the productive period is required for a niche market sustaining and encouraging biodiversity and the peculiarities of the products that consumers can appreciate. Egg production and quality of the eggshell and albumen in fresh and stored eggs of two Italian dual-purpose purebreds (Ermellinata di Rovigo (ER); Robusta maculata (RM)) and two hybrid genotypes (Hy-Line Brown (HB); Hy-Line White (HW)) reared outdoors were compared throughout the laying period. RM breed (brown eggshell) showed fresh and stored eggs with a good eggshell thickness, and Haugh Units (HU) quite stable along the production period; RM total egg mass was lower than ER (light brown eggshell) which showed fresh and stored eggs with more variable HU, due also to a possible effect of lower eggshell thickness and pigmentation, and shape index. The hybrids produced a higher total egg mass than the purebreds and showed an intermediate variation of the egg quality, with HU higher than those of ER and RM only in 1 d eggs, but not in stored eggs. ABSTRACT: The quality of fresh (1 d) and stored (7–14–21 d, 21 °C) eggs was studied in Italian dual-purpose breeds (Ermellinata di Rovigo (ER), Robusta maculata (RM)) and hybrids (Hy-Line Brown (HB), Hy-Line White36 (HW)), reared outdoors (4 m(2)/bird) and fed commercial feed. The eggs were analyzed at 4 ages, throughout different seasonal environmental conditions, from summer (31, 35 weeks; 25 °C) until autumn (39, 43 weeks, 15 °C). Each genotype showed significant (p < 0.01) changes in egg quality. In 1 d eggs, the eggshell thickness changed in RM and HW (quadratic), decreased linearly in ER; Haugh Units (HU) changed (ER–cubic) and decreased (hybrids-linear). In 7 d and 14 d eggs, HU linearly (p < 0.01) decreased, except in RM. In 21 d eggs, HU (ER linear decrease; HB, HW quadratic) changed. Significant negative correlations between albumen pH and height were seen in ER (at 1 d, 14 d, 21 d) and HW (at each storage time) eggs, and in RM and HB only in 1 d eggs. RM showed a quite stable albumen quality and a lower total egg mass than ER which showed a more variable albumen quality, due also to a lower eggshell thickness and shape index. The hybrids produced a higher total egg mass than the purebreds and showed an intermediate variation of the egg quality, with an albumen quality higher than those of ER and RM only in 1 d egg, as a result of a higher albumen weight.