complete introduction to milk making production line

The entire liquid milk production line is divided into seven sections: raw milk receiving → pretreatment → standardization → homogenization → sterilization and cooling → filling and packaging → later storage and cleaning. All equipment is made of food grade 304/316 stainless steel and equipped with a fully automatic CIP in-situ cleaning system. It is divided into two mainstream solutions: pasteurized fresh milk production line (short-term refrigeration) and UHT room temperature sterilized milk production line (long-term room temperature).

1、 Complete process flow
1. Raw milk receiving, inspection and storage
Process objective: To inspect qualified raw materials, quickly lock freshness and inhibit bacteria
1. Milk tanker sampling and testing: acidity, fat, protein, bacterial count, antibiotics, sensory perception
2. Unloading pump conveying, dual filter for preliminary filtration of hair and impurities
3. Send it to the refrigeration milk storage tank and quickly cool it down to 0-4 ℃ for temporary storage
Supporting equipment: milk pump, filter, horizontal vertical insulation refrigeration tank, online sampler

2. Pre treatment section
1. Centrifugal Milk Purification: The high-speed centrifugation of the milk purifier removes small impurities, somatic cells, and some bacteria
2. Degassing: The deaerator removes air from the milk to prevent fat oxidation and foaming during filling
3. Preheating and heating: The plate heat exchanger is heated to 45-60 ℃ to meet the homogenization process temperature

3. Standardization (precise blending of ingredients)
By using a cream separator to separate milk into skim milk and cream, and then accurately blending according to product standards, the fat and protein content is fixed to ensure that each batch of milk has consistent indicators; Skimmed milk can be produced separately.

4. High pressure homogenization
Equipment: High pressure homogenizer, pressure 15-25MPa
Crush coarse fat globules to avoid cream floating during storage; The finished product has a smooth taste, uniform color, and is not easily layered.
>Process conditions: The best homogenization effect is achieved at a temperature of 45-60 ℃


5. Sterilization section (two core routes)
Route A | Pasteurized milk (fresh milk, requires 0-4 ℃ cold chain)
-HTST high temperature short-term: 72~75 ℃/15? 20s; or 85 ℃/15s
-Kill pathogenic bacteria, preserve natural flavor and active nutrients to the fullest extent
-Quickly cool to 2 after sterilization? 4℃
-Shelf life: 7-15 days
-Filling environment: Class 10000 clean workshop, roof box, glass bottle, plastic bag packaging

Route B | UHT Ultra High Temperature Instant Sterilized Milk (Constant Temperature Pure Milk)
-Process: 135-140 ℃, insulation 2? 4 seconds, instant commercial sterilization
-Vacuum rapid cooling to room temperature (20-25 ℃)
-The entire process is filled in a sterile environment, and the finished product does not require refrigeration, with a shelf life of 6 days? 9 months
-Packaging: Tetra Pak sterile bricks, sterile PET bottles, sterile bags






6. Filling and sealing
1. Clean filling of pasteurized milk: roof box filling machine, glass bottle washing, filling and sealing integrated machine, bag filling machine
2. UHT aseptic filling: aseptic paper wrapping machine, aseptic blowing and filling rotary machine, pre sterilized packaging materials with hydrogen peroxide, and filling chamber maintained at level 100 sterility
3. Automatic sealing, coding, production date, batch number




7. Post processing and warehousing
-Labeling and lamp inspection (checking for missing or foreign objects)
-Automatic packing, robot palletizing and warehousing
-Is pasteurized milk delivered to 0? 4 ℃ refrigerated warehouse; UHT milk storage at room temperature




8. CIP in-situ automatic cleaning (essential for dairy production lines)
Fully automatic cleaning after production, no need to disassemble:
Pre flushing water → alkaline circulation cleaning → rinsing with clean water → acid washing to remove scale → final rinsing with clean water+disinfection
Prevent the growth of bacteria in milk stains, ensure food safety, and meet food production standards


2、 Comparison Table of Two Production Lines
|Project | Pasteurized Fresh Milk Production Line | UHT Room Temperature Milk Production Line|
|---|---|---|
|Sterilization parameters | 72? 85℃，15?20s|135? 140℃，2?4s|
|Storage conditions | Full process 0? 4 ℃ refrigeration | stored at room temperature|
|Shelf life | 7? 15 days | 6? 9 months|
|Filling level | Clean filling | Aseptic filling|
|Investment cost | Medium | High (expensive sterile equipment)|
|Product features | Fresh flavor | Wide circulation range, no need for cold chain|


3、 List of complete production line equipment
1. Raw material receiving system: discharge pump, dual filter, refrigeration milk storage tank
2. Pre treatment: Milk purifier, deaerator, plate heat exchanger
3. Standardization: centrifugal separator, mixing tank
4. Homogenization: High pressure homogenizer
5. Sterilization system: Plate pasteurizer/UHT tube sterilization unit
6. Filling System: Roof Box/Glass Bottle/Tetra Pak Aseptic Filling Machine
7. Backend packaging: coding machine, labeling machine, packing machine, palletizing robot
8. Auxiliary systems: fully automatic CIP cleaning station, industrial control central control system, refrigeration unit


4、 Expand derivative product transformation
Replacing the backend process on the same basic production line can produce other dairy products:
-Yogurt: After sterilization, cool down to 42 degrees Celsius? 45 ℃, inoculated with bacterial strains for fermentation
-Blended milk/flavored milk: adding sugar blending tanks and online mixing systems
-Milk powder: add evaporation concentration and spray drying sections