Quality of Japanese quail (Coturnix coturnix japonica) eggs after extended refrigerated storage
J.K. Northcutt, A. Buyukyavuz, Paul A. Dawson
Abstract
Commercial Japanese quail (Coturnix c, japonica) eggs were stored for 0, 30, 60, 90, and 120 d at 4°C to determine the effects of storage on egg quality. Total aerobic microorganisms (APC) and yeast and mold (YM) were recovered from the same eggs using 3 different methods, including an eggshell surface rinse, eggshell crush rinse, and contents enumeration. Both APC and YM on eggshell surfaces decreased by 87% (0.9 log reduction) from 0 d to 120 d of storage. APC from crushed eggshells ranged from 2.4 to 3.1 log cfu/egg. YM were not detected in crushed eggshells until 120 d of storage where levels were 1.3 log cfu/egg. Aerobic microorganisms were found in contents of eggs stored 30, 60, or 90 d, but no YM were not detected in egg contents. Albumen pH increased from 0 to 30 d of storage (pH 8.91–9.22). Similarly, the largest decrease in albumen height was between 0 (3.9 mm) and 30 d (3.4 mm) before decreasing to 2.5 mm after 120 d storage. Yolk pH also increased with longer storage times, but the most significant increase occurred between 90 and 120 d of storage (0.49 pH unit increase). Similarly, Haugh units (HU) decreased with longer storage time, with the most significant changes occurring between 90 and 120 d of storage where HU decreased by 3.7. Overall, quail eggs stored for up to 120 d at 4°C had HU values above 72, placing them at AA grade by USDA standards. Findings may be of commercial interest to quail egg producers as a part of their marketing strategy.