Micellar casein powders (MCP) are added to food products to enhance their protein content and functional qualities. Enzymatic cross-linking (CL) with microbial transglutaminase (mTGase) is a promising method for improving the functional properties of MCP. Non-cross-linked (N-MCP) and enzymatically cross-linked (C-MCP) at different CL degrees (0, 36, 48, and 58 %), were evaluated to assess the changes in MCP powder solubility after storage at two temperatures (25 and 40 °C) for up to 180 days. The MCP were examined periodically to determine the browning index (BI), the loss of solubility, the variations in the wetting time, and the morphological surface composition evolution with aging. The solubility of both N-MCP and C-MCP decreased similarly with storage, and this phenomenon was enhanced by increasing the severity of the storage (temperature and time). Based on changes in the BI and solubility loss, N-MCP and C-MCP have similar aging kinetics. According to relaxation time analysis, the CL degree reduced the interaction between the powder particles and the solvent, which further diminishes with storage. The results suggest that CL would trigger changes in the MC powder surface, but the evolution of the functional properties is not related to the storage-induced CL formation.