A solution for on-farm milk cooling was assessed under controlled laboratory conditions. The basic principle is to use insulated milk cans with an integrated ice compartment for the transport of morning milk and the storage of evening milk with a maximum capacity of 30 L milk and 8 kg ice. The experimental results show the ability of the system to cool down 30 L milk to 17°C in less than 90 min with 6 kg ice. By using the same milk-can with 20 L and 8 kg ice, milk remains below 13°C over 12 h at 35°C ambient temperature. In both cases, the proliferation of bacteria was effectively prevented for 3.5 and 12 h, respectively. A computational model was developed and fitted to the experimental results in order to predict cooling curves of other milk/ice ratios and ambient temperatures. Furthermore, the possibility of using water as low-cost substitute for milk for research purposes was analyzed experimentally.
Published in International Journal of Refrigeration, Volume 90, June 2018, Pages 22-31