Thermostability of Hen Egg Yolk Granules: Contribution of Native Structure of Granules

• Published in: Journal of food science Vol. 65; no. 4; pp. 581 - 584
• Main Authors: Anton, M., Denmat, M. Le, Gandemer, G.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01-05-2000; Institute of Food Technologists; Wiley Subscription Services, Inc; Wiley
• Subjects: Biological and medical sciences; Egg and egg product industries; egg yolk; Eggs; emulsion stability; Food industries; Food science; Fundamental and applied biological sciences. Psychology; granule structure; heat treatment; Life Sciences; Poultry; protein aggregation; Proteins; Viscosity; Egg yolk; Heat treatment; Oil water emulsion; Denaturation; Emulsifying power; Solubility; Protein; Aggregation; Egg product; Animal protein; Technological properties; Thermotolerance; Rheological properties; STABILITE
• ISSN: 0022-1147; 1750-3841
• DOI: 10.1111/j.1365-2621.2000.tb16052.x

To understand why protein granules resist heat treatment, we measured denaturation, viscosity, and solubility of heated native and disrupted granules and estimated the effect on their emulsifying ability. Granule disruption by sodium chloride caused protein solubility to drop dramatically and viscosity to rise sharply above 72° C. Solubility of native granules was unaffected by heat, and viscosity increased slightly. Electrophoresis revealed that, whatever the granules structure, low‐density lipoproteins (LDL) and α‐high‐density lipoproteins (α‐HDL) were denatured, whereas phosvitin and β‐HDL were resistant to heat. Disrupted granules provided weaker emulsifying ability than native granules. The structure of native granules cannot prevent protein denaturation but can avoid aggregation of LDL and α‐HDL from different granules.