During transport dry milk products are subjected to high temperature fluctuations. However, it is important that the quality of the product is always the same and does not change during transport. The influence of temperature fluctuations in the shipping container on the quality of the product is reduced by a close packing of the product and by suited thermal properties of the dry products.
The thermal properties are affected by the composition, density, porosity, fat and water content of the powder. For a good product a high specific heat capacity and a low thermal conductivity is needed.
The thermal conductivity of a milk powder was measured by THB-100 (new model THB Basic, Advance, Ultimate) at room temperature and 60 °C.
For that, the milk powder was dissolved in distilled water and the sensor (metal frame sensor) was hung into the liquid.
For the measurement at 60 °C, the sample was heated up in a furnace. The thermal conductivity of the sample decreases slightly from 0.61 W/mK to 0.59 W/mK in the measured temperature range. Thus, the milk powder has a low thermal conductivity as the thermal conductivity of water at room temperature is 0.60 W/mK.
