Formation mechanism and inhibition methods of frozen egg yolk gelation: A review

Background Egg yolk is a nutrient-rich ingredient widely utilized in various food products including mayonnaise, salad dressings and cakes. Freezing could address the issue of microbial contamination and quality deterioration of liquid egg yolk during prolonged storage and transportation, which helps to preserve the nutrient content of the yolk and extend its shelf life. However, freezing could cause irreversible changes in the flowability and viscosity of egg yolk, resulting in a phenomenon known as gelation, making it difficult to mix egg yolk with other food ingredients and reducing its dispersibility and functionality. Scope and Approach Based on the phenomenon of frozen egg yolk gelation, this paper focuses on the current research status regarding the gelation mechanism of each component in egg yolk, including the formation of ice crystals, protein denaturation and aggregation, and molecular interactions. Meanwhile, the principles underlying various methods used to inhibit gelation are discussed, encompassing physical, chemical, and enzymatic approaches. Key Findings and Conclusions These methods inhibit frozen egg yolk gelation by different mechanisms. Comprehending the research progress of gelation and its inhibition methods can offer valuable insights for future research and the application of frozen egg yolk in food production.