The impact of storage temperature and duration on the microbiological safety, quality, and shelf-life of Banat Naked Neck hen eggs before expiration

Temperature is a major determinant of egg quality loss, but data for Banat Naked Neck hens are limited. This study evaluated 240 freshly laid eggs stored for 28 days at room temperature (RT, 20-22°C) or under refrigeration (RF, 4-6°C). Egg mass, shell deformation and breaking strength, shell weight and thickness, albumen height, Haugh units (HU), yolk colour, and albumen and yolk pH were measured on days 1, 7, 14, 21, and 28; preliminary screening for determine the total bacterial count, Salmonella spp. and Listeria monocytogenes was also performed. The egg mass remained stable. Albumen height significantly dropped by 35.18% under RF and by 57.58% at RT when compared to the first and last day of the four-week storage period, while HU declined from 80 to 62 under RF and from 81 to 46 at RT (p < 0.05). Shell breaking, shell thickness and yolk colour showed no significant variation. Albumen pH increased to 9.14 under RF and 9.37 at RT (p < 0.05), and yolk pH increased more slowly yet followed the same temperature-dependent trend (p < 0.05). No target pathogens have been detected in either treatment to date. A gradual increase in total bacterial count was observed during the storage period, with a significant difference (p < 0.05) observed on day 28. Our results show the need for the perseverance of the intact cold chain and proper storage within the recommended shelf life to preserve the optimal quality and safety of eggs.