Original Scientific Article
Influence of relative humidity on internal quality, bacterial load, and mold contamination of eggs during 28-day storage
Ahmet Yavuz Pekel * ,
Alp Emre Yıldız ,
Abdurrahman Kızıl ,
Ali Aydın

Mac Vet Rev 2026; 49 (2): i - xi

10.2478/macvetrev-2026-0022

Received: 12 March 2026

Received in revised form: 04 June 2026

Accepted: 11 July 2026

Available Online First: 27 July 2026

Published on: 15 October 2026

Correspondence: Ahmet Yavuz Pekel, pekel@iuc.edu.tr
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Abstract

This study analyzed the effects of varying relative humidity (RH) on the internal and microbiological quality of eggs stored at ambient temperature (22±2°C) for 28 days. Medium-sized eggs, produced by 60-week-old Lohmann Brown hens (n=30), were selected randomly and allocated into sealed chambers set to 20%, 60%, or 100% RH. Egg weights were measured weekly, while internal quality attributes were evaluated at the conclusion of the storage duration. Eggs stored at 20% RH exhibited the highest weight loss (5.9%), whereas those at 100% RH showed minimal moisture loss (0.39%). Eggs stored at 20% RH also exhibited the highest yolk redness. Compared to 96.7% and 100% in the 60% and 20% RH groups, respectively, only 36.7% of eggs stored at 100% RH remained organoleptically acceptable for consumption after 28 days, based on predefined classification criteria. The 60% RH condition resulted in the poorest albumen structure, as reflected by the lowest Haugh unit scores. The length and width of the albumen decreased at 20% RH, while yolk pH remained unaffected by the humidity level. The yolk index declined as humidity increased. Eggs stored at 100% RH harbored the highest microbial loads, including mold, yeast, and aerobic bacteria, whereas the lowest shell contamination was observed at 20% RH. No significant differences in microbial counts were identified between the 20% and 60% RH groups. In conclusion, storage at low humidity (20%) was associated with better preservation of selected quality whereas saturated humidity (100%) was associated with significant quality deterioration and an increased risk of contamination.

Keywords: relative humidity, internal quality, eggshell microbial activity, egg color

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Copyright  

©2026 Pekel A.Y. This is an open-access article published under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Conflict of Interest Statement

The authors declared that they have no financial or non-financial conflict of interest regarding authorship and publication of this article.

Citation Information

Macedonian Veterinary Review. Volume 49, Issue 2, Pages i-xi, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI:  https://doi.org/10.2478/macvetrev-2026-0022

The all content of the Macedonian Veterinary Review, except where otherwise noted, is licensed under a Creative Commons Attribution License.