While tissue stiffness has long been the primary indicator for the presence of diseased tissue, stiffness does not give the full picture of the actual mechanical properties seen in tissues. Viscoelasticity is believed to better represent the actual tissue mechanical properties however it remains challenging to measure this property at a cell scale with current methods such as elastography. Using thermally actuated expanding hydrogel beads, we've developed a platform for measuring viscoelasticity by measuring the time dependent expansion of beads embedded within a tissue. By cold shocking the sample, bead-based sensors are quickly activated allowing the creep behaviour of viscoelastic materials to be observed. This model has allowed us to theoretically measure viscoelastic properties is tissue by comparison to finite element simulations. When applied in live and fixed tissues, fixed tissues were observed to be mostly linearly elastic with negligible time dependence of sensors expansion compared to live tissues. Furthermore, changes in the viscoelasticity of inducible breast cancer model confirmed the hypothesis that invasive tissues undergo changes in their mechanical properties. This technology could potentially be used in the future for advanced screening of breast cancer to tailor aggressiveness of the treatment given to the behaviour of the disease.