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Updated: Jun 30, 2026
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Mechanical Separation and Protein Solubilization of the Outer and Inner Perivitelline Sublayers from Hen's Eggs
Published on: January 27, 2021
Physical-mechanical modifications of eggs for food-processing during storage.
A Berardinelli1, L Ragni, A Giunchi
1Economy and Engineering Agricultural Department, University of Bologna, Piazza G. Goidanich, 60-47023, Cesena (FC), Italy. annachi.berardinelli@unibo.it
Poultry Science
|September 24, 2008
Summary
Egg quality declines significantly with extended post-refrigeration warming. A week at 18°C after cold storage drastically reduces albumen height, Haugh units, yolk index, and membrane strength.
Area of Science:
- Food Science
- Animal Science
- Agricultural Science
Background:
- Egg quality is crucial for food processing, particularly for mechanical shelling.
- Physical-mechanical properties of egg constituents change during storage and post-storage.
- These changes impact processing efficiency and product yield.
Purpose of the Study:
- To analyze the physical-mechanical properties of egg constituents.
- To evaluate modifications during extended storage and various post-storage treatments.
- To determine the impact of these changes on egg processing.
Main Methods:
- Eggs from Hy-Line White and Lohmann Brown hens were stored at 0°C for 7 months.
- Post-storage treatments included immediate analysis (T1), 6 hours at 18°C (T2), and 1 week at 18°C (T3).
- Analyzed parameters included thick albumen height, Haugh unit, yolk index, and vitelline membrane-yolk system strength.
Main Results:
- All qualitative parameters significantly decreased with the week-long post-storage warming treatment (T3).
- Mean decreases were approximately 19% (albumen height), 14% (Haugh unit), 14% (yolk index), and 16% (membrane strength) compared to T1.
- Vitelline membrane-yolk system strength decreased by about 10% during 7 months of cold storage.
Conclusions:
- Extended post-storage warming at 18°C is detrimental to egg quality and physical-mechanical properties.
- Storage at 0°C also leads to a gradual decline in egg strength over time.
- Understanding these changes is vital for optimizing egg processing and maintaining quality.
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