1. Direct-Cooling Milk Cooling Tank

Direct-cooling tanks extract heat from the milk through an evaporator that comes into direct contact with the liquid. The advantages of this method include rapid cooling and high efficiency, allowing the milk to reach the target temperature quickly. However, because the evaporator directly contacts the milk, strict attention must be paid to the material of the evaporator and to hygiene standards to prevent contamination. Additionally, maintenance costs are relatively high, as the evaporator requires regular cleaning and disinfection.

2. Indirect-Cooling Milk Cooling Tank

Indirect-cooling tanks operate by circulating a cooling medium (such as water or antifreeze) through a jacketed space between the evaporator and the tank wall; heat is transferred from the milk to the cooling medium, which then carries the heat away. The advantages of this method are that it avoids direct contact between the evaporator and the milk-thereby reducing the risk of contamination-and facilitates the treatment or replacement of the cooling medium. While the cooling rate is relatively slower, the process is gentler, making it suitable for applications where milk quality is a high priority.