Development of a 3D-bioprinted wheat gluten-based scaffold functionalized with citric acid for cultured meat...

The commercial viability of cultivated meat depends on the development of edible, low-cost scaffolds that provide suitable biomechanical cues for cell maturation. This study developed and characterized a food-grade composite bioink based on wheat gluten (10.8% w/w), sodium alginate (6.5% w/w), and carboxymethylcellulose (3.2% w/w), functionalized with citric acid for 3D bioprinting. Two formulations were evaluated: Control (BC) and Modified with citric acid (BM). Rheological characterization confirmed a non-Newtonian shear-thinning behavior (n = 0.14 to 0.22) for both groups, promoting shape fidelity. FTIR and DSC analyses evidenced that citric acid acted as a green crosslinker, promoting a stabilized polymeric network through enhanced hydrogen bonding and the potential formation of covalent ester bonds. Citric acid also served as an in situ porogen, increasing total porosity from 34.4% to 44.0% and creating an interconnected microarchitecture. This structural shift allowed the matrix to overcome the classic trade-off between porosity and strength, maintaining hardness while increasing resilience (∼20%) and gumminess (∼45%). Biological validation with porcine epithelial cells (IB-RS-2) and murine myoblasts (C2C12) confirmed cytocompatibility. While IB-RS-2 exhibited confluence and maintained metabolic activity over 7 days, C2C12 myoblasts showed increased cell density and morphological variation in regions in proximity to the scaffold. These observations suggest active cell-material interaction, although further studies are required to determine specific differentiation pathways. These findings establish the functionalization of gluten with organic acids as a sustainable, scalable, and low-cost platform for the biofabrication of scaffolds in the cultivated meat industry.