1 - Start
Milk initially arrives at the balance tank, where the purpose is to ensure a continuous supply of milk in the line. In other words, milk is taken into the balance tank to stabilize its entry into the pipeline.
2 - 1st Regeneration
With the help of pumps, milk enters the first regeneration section of the pasteurizer. The milk arriving at the 1st regeneration section encounters milk that has previously been pasteurized and reached a high temperature. Since there are plates between the two different types of milk, they do not come into direct contact. The temperature of the cold milk, encountering the pasteurized milk, reaches 55°C. The milk, reaching this temperature, exits the 1st regeneration and is sent to the separator.
3 - Separator
The reason milk is sent to the separator at this stage is to reach the optimal temperature for cream separation. The cream is separated from the milk that has left the 1st regeneration and gone to the separator. (This standardizes the fat content to the desired level.)
4 - 2nd Regeneration
The milk, with its fat content standardized, goes to the 2nd regeneration section. This milk encounters the milk coming from the holding tube. (What a holding tube is will be explained in later stages.) At this stage, the temperature of the milk reaches between 60-70°C.
5 - Heater
In the following stage, milk reaches the heating section where it is heated with hot water. This process gradually increases the temperature of the milk to the exact pasteurization temperature.
6 - Holding Tube
Milk that has reached the pasteurization temperature is sent to the holding tube mentioned in step 2. The milk is held there for a certain period to ensure the destruction of harmful microorganisms. It consists of a long pipe system with a zigzag heat holding pattern. The aim of this process is to maintain the milk at the pasteurization temperature for a set duration. This period is approximately 15 seconds. (The milk coming from the holding tube mentioned in step 4 is the milk that comes out here.) At the end of the holding tube, there is a thermometer and a valve. If the milk's temperature is not at the correct level, the valve automatically activates, and the milk is returned to the start of the pasteurizer for repasteurization and to circulate through the system again.
7 - 1st and 2nd Regeneration
If there are no issues with the temperature, the milk exiting the heat holder is sent back to the 1st and 2nd regeneration section. The milk arriving here cools down the pasteurized milk by encountering raw milk. As the pasteurized milk cools down, the newly entered raw milk into the system gets heated up. This allows for a significant recovery of energy.
8 - Cooler
Finally, the pasteurized milk moves to the cooling section where it is cooled down with ice water.
Energy Recovery in Pasteurization
The most crucial point of the pasteurization process is the section where we increase the temperature of the incoming raw milk to 65°C using the pasteurized milk we have processed. After this stage, the milk that has reached 65°C only needs to be heated by another 35°C to reach 90°C. A significant energy saving is achieved since the raw milk is heated from its initial temperature to 65°C using the 90°C pasteurized milk we have already heated.