Dense collagen matrices, crafted through automated gel aspiration-ejection (GAE), offer exciting potential in the field of biofabrication. This study illuminates the crucial role fibrillization pH plays in both the real-time rheological changes during collagen hydrogel gelation and the properties of the resulting biofabricated matrices. Findings demonstrate a relative increase in hydrogel stiffness with higher gelation pH, with matrices demonstrating increased fibrillar density, alignment, and micro-compressive modulus at specific pH levels. Importantly, these matrices showed low cell mortality when seeded with fibroblasts. These findings may offer valuable insights applicable to other hydrogel systems and biofabrication techniques.