Effect of diet composition on egg white heat-induced gel properties of Roman laying hens: from phenomenon, substance, structure to mechanism

Abstract Multidimensional impact of diet composition on egg quality and function has become a research hotspot in the laying hen industry. However, there were relatively few reports on the effect of diet composition on the composition of egg white and its heat-induced gel behavior. Based on this, the system compared the differences in Roman egg white heat-induced gel behavior, protein composition, molecular conformation and molecular interaction under the dietary models of corn distillers’ grains, corn and soybean meal and flaxseed, revealing the potential influence mechanism of dietary composition on heat-induced gel behavior. The results indicated that the egg white protein gel under the corn and soybean meal diet pattern had the best gel properties, with hardness and water holding capacity significantly increased by 23.1% and 2.0% respectively compared to the corn distillers’ grains diet pattern. The improvement in the gel behavior might be attributed to the changes in the material composition of egg white proteins (increased protein and amino acid contents), protein aggregation state (reduced particle size and weakened aggregation), molecular structure (increased β-sheet relative content and decreased thermal denaturation temperature), and intermolecular interactions (enhanced hydrophobic interactions and disulfide bonds). These findings will provide a scientific basis for regulating the performance of egg heat-induced gel from the nutritional source of laying hens and for the development of customized egg products.