Formed constant temperature boundary with constant temperature bath and combined with the brass short cylindrical sample box, the formation of multi-dimensional heat flow is guaranteed in the test sample. The unsteady thermal conductivity multiplication method and parameter estimation method were used to calculate the thermal conductivity and specific heat capacity of grain. At the same time, considering the effect of opening holes on the thermostat, and increasing the difficulty of experimental operation, the ZigBee wireless data acquisition module is used for signal acquisition and transmission. By analyzing the thermophysical parameter sensitivity analysis of corn and paddy, the sensitivity coefficient of specific heat capacity is found to be low. In view of this, the calculation system first estimated the thermal diffusivity, and then compared the results of heat capacity estimation. An experimental test device was set up to calculate the thermal properties of four kinds of food including “Wandao 121”. The results were consistent with the relevant literature. At the same time, the thermal properties of “Wandao 121”, the theoretical calculation and the numerical simulation were used to monitor the temperature rise over time. The results show that the theoretical trend of temperature rise is consistent with the measured temperature rise, further verifying the value of the parameter estimation accuracy and reliability.