###### Abstract  
To improve the mechanical strength and oil-loading performances of egg white protein (EWP) aerogel, the effects of different grafting degrees on the modification of EWP by sodium carboxymethylcellulose (CMC-Na) were investigated. After different dry-heat treatment durations (0, 12, 24, 36, and 48 h), the EWP/CMC-Na conjugates with different grafting degrees (noted as EC\({}_{0}\), EC\({}_{12}\), EC\({}_{24}\), EC\({}_{36}\), and EC\({}_{48}\), respectively) were obtained. Subsequently, the physicochemical properties of the conjugates, as well as the microstructure, mechanical properties, pore parameters, emulsification properties and oil-carrying properties of the conjugated aerogels, were characterized. The results showed that EC\({}_{12}\) (with a grafting degree of 8.35%) aerogel possessed a uniform structure, the largest specific surface area, and the best emulsification performance. This facilitated a more robust aerogel (2.05 MPa) with nearly three times the mechanical strength of EWP aerogel. Moreover, this had a positive influence on the efficient loading and stable retention of oil. EC\({}_{12}\) aerogel thus achieved an oil absorption capacity of 5.46 g/g aerogel and an oil holding capacity of 31.95%, and both values were nearly 1.7 times higher than those of EWP aerogel. In general, the EWP-based aerogel with a grafting degree of 8.35% had the best mechanical and oil-loading properties. protein-based aerogel; oil absorption; mechanical strength; egg white protein; sodium carboxymethylcellulose  
17 December 2021  
Accepted: 9 February 2022  
15 February 2022  
groups they carry on their molecules (e.g., thiol, hydroxy, amine, amide, and carboxyl groups) endow aerogels with the potential for extended chemical functionalities and easier functionally oriented customization. Certain proteins, including whey and silk protein, have been used as aerogel precursors in related fields [18; 19]. Egg white protein (EWP), an important component of poultry egg protein, is also known for its excellent gelation properties. Its consistency and texture can especially be improved by gelation processes, which also provide corresponding nutrition and flavor benefits [20]. To further expand the application of EWP in different fields and to enhance its added value, many efforts have been made regarding gels and aerogels [21; 22; 23]. In recent years, ideogletion has been widely used as a novel and efficient strategy to study the structuring of liquid oils and fats. Oleogels are considered to be semi-solid systems that consist of a network structure formed by a polymer with a hydrophobic liquid (e.g., oil). Thus far, several techniques have been developed for the preparation of oleogels. On the one hand, gelators, including natural waxes and cellulose derivatives [24; 25], have been used to self-assemble into continuous three-dimensional networks and to immobilize liquid oils and fats by means of their surface tension and capillary forces. However, they mostly have a \"waxy\" texture and some gelators such as 12-hydroxyate acid are not allowed to be used in food. On the other hand, the techniques of indirect oleogletion using emulsions and hydrogels as templates have been exploited [26; 27], whereas further high-temperature drying or solvent exchange treatments limit their far-reaching development. However, the single EWP gel network structure and its texture do not meet current demands for the formation of protein-based aerogels. For desirable oil-loading matrices, EWP aerogels are required to achieve high mechanical properties and loading efficiency to broaden their applicability [23; 28]. Therefore, improving the mechanical performance and loading efficiency of EWP aerogels are urgent problems to be solved.