The influence of glucono-δ-lactone on pea-based 3D printing meat analogues: rheological properties, printing properties and textural properties

This study investigated the effects of glucono-δ-lactone (GDL) on the properties of printable inks and meat analogues formulated from pea protein and chicken protein. The results demonstrated that GDL significantly modified the rheological properties of the printing ink, enhancing its shear-thinning behavior and viscoelastic modulus, which are critical for precise extrusion and shape retention during 3D printing. By optimizing the GDL concentration, we achieved a significant improvement in printing accuracy. Specifically, the 0.4% GDL sample exhibited the lowest dimensional deviation (30.78 ± 1.72%) and cooking shrinkage rate (11.36 ± 0.89%). Compared to the control (0% GDL), GDL significantly enhanced the textural properties of the printed meat analogues: hardness increased by 35.9%, elasticity by 35.27%, and chewiness by 45.2%. Concurrently, the water loss rate and cooking loss decreased by 58.17% and 31.63%, respectively, due to GDL-induced crosslinking. SEM revealed that 0.4% GDL induced a uniform porous microstructure due to balanced crosslinking, which physically entrapped water through capillary forces and provided structural resistance, directly enhancing textural properties such as hardness and chewiness. FT-IR and intermolecular force analysis indicated that GDL strengthened hydrophobic interactions and disulfide bonds, thereby enhancing the structural stability of the printed meat analogues. Sensory evaluation indicated that the 0.4% GDL sample had the highest meat similarity score due to its superior texture, juiciness, and overall sensory characteristics. These findings provide valuable insights into the application of GDL in 3D food printing and the development of high-quality plant-based meat analogues.