Concentrated calcium caseinate dispersions can be transformed into hierarchically fibrous materials using shear deformation. The resulting material is relevant for its structural resemblance to meat, which has a potential to be a basis of new meat analogue products. Thus, calcium caseinate can be used as a model system for studying fibrous structure formation. Overall, the research established that fibrous structure formation under well-defined shear flow is enhanced by air bubbles. In case of spray-dried calcium caseinate, the high anisotropy is caused by a combination of the anisotropy in the protein phase and the additional effect of air. The effect of air is a result of air bubble alignment with air bubbles remaining mostly spherical. However, the presence of largely elongated air bubbles in an isotropic matrix could still induced fibrous appearance and mechanical anisotropy when using roller-dried calcium caseinate.