Development of high protein 3D printed dysphagia salmon analogs based on walnut protein-egg white protein emulsion gels.

Dysphagia in the elderly causes inadequate nutrient intake, particularly protein. 3D food printing offers a promising solution by producing customized nutrient-rich foods. To develop 3D-printed salmon analogs, walnut protein (WP)-egg white protein (EWP) emulsion gels were used. Higher EWP content improved printability due to increased mechanical strength and a denser microstructure formed through hydrogen bonding. Subsequently, the effects of pre-processing (baking and steaming) on 3D-printed analogs were investigated. Products baked for 3 min scored highest in sensory attributes (salmon-like color, roasted/fatty flavors, texture, swallowing smoothness). Baking induced a reddish, darker color (likely from Maillard reaction), while steaming brightened the products. Notably, all products met Levels 4-6 of the International Dysphagia Diet Standardization Initiative (IDDSI). Furthermore, baking increased key aroma compounds (eg. 1-octen-3-one), while steaming elevated aldehydes, alcohols, and sulfur-containing compounds. Therefore, baked for 3 min was identified as optimal treatment, supporting 3D-printed food development for dysphagic elderly.