Rheological behavior of egg yolk: Processing impacts and applications in food systems

Abstract

Egg yolk (EY) is a nutrient-dense, multifunctional food ingredient with complex rheological behavior that is critical for its performance in emulsions, sauces, and baked goods. This review consolidates and analyzes current knowledge on how food processing techniques, including freezing, thermal treatments, ultrasound, high-pressure processing (HPP), microfluidization, as well as additives like hydrocolloids, alter EY rheology and its subsequent applications in food systems. Key findings reveal that processing induces structural changes (e.g., protein denaturation, aggregation, gelation) which modify key rheological properties like viscosity, viscoelasticity, and shear-thinning behavior. For instance, thermal processing above 80 °C transforms yolk into a solid-like gel, which is crucial for