Fully automatic yogurt production line

complete introduction to yogurt production line
The yogurt production line is divided into four mainstream processes: stirred yogurt, solidified yogurt, drinking yogurt, and room temperature sterilized yogurt. The entire line is made of SUS304/316 food grade stainless steel, with PLC automatic temperature control and online CIP/SIP cleaning. The entire process is sealed and sterile, controlling the three core parameters of fermentation pH, temperature, and time.

1、 Comparison of complete process flow
1) Blended yogurt (fruit yogurt, regular cup yogurt, mainstream on the market)
Raw material acceptance → milk collection and temporary storage → filtered and purified milk → standardization (adjusting fat/solids) → ingredient sugar/stabilizer dissolution → preheating → high-pressure homogenization → pasteurization → cooling to inoculation temperature (42-43 ℃) → adding lactic acid bacteria → fermentation in insulated fermentation tanks → emulsion breaking and stirring → cooling (15-22 ℃) → online mixing of fruit/jam → buffer temporary storage → sterile filling → coding and packaging → 0-5 ℃ refrigerated outbound
2) Solidified yogurt (aged yogurt with curd inside the cup)
Raw material pretreatment → sterilization and cooling → inoculation of bacterial strains → filling and sealing cup first → sending to constant temperature fermentation chamber for fermentation → rapid cooling → refrigerated storage
3) Room temperature yogurt (shelf life of 6 months)
After fermentation is completed, UHT ultra-high temperature sterilization is carried out for aseptic filling, without the need for cold chain storage.

2、 Detailed explanation of segmented process and supporting equipment
1. Raw material receiving and pretreatment section
Equipment: Milk collection tanker, measuring tank, refrigeration milk storage tank, dual filter, centrifugal milk purifier, ingredient tank, high shear dissolution system
-Raw milk testing: fat, protein, acidity, antibiotics, bacterial colonies; Qualified fresh milk is quickly cooled to 2-4 ℃ and stored for insulation
-Standardization: Defatting/topping through a separator; Adding stabilizers such as sugar, whey powder, pectin, gelatin, etc. to enhance viscosity
-Degassing: remove milk bubbles to avoid foam and pores in finished products

2. Homogenization section
Equipment: High pressure homogenizer
-Preheat to 50-60 ℃, pressure 15-20MPa; Crush the fat globules to<2 μ m
-Function: prevent fat from floating, smooth texture of yogurt, reduce whey precipitation

3. Sterilization section
Equipment: Plate Pasteurization Machine (HTST)/Tube Sterilization Machine
1. Low temperature refrigerated yogurt: 90-95 ℃/5-300s, kills miscellaneous bacteria, inactivates natural enzymes in milk, and retains live bacteria
2. Room temperature yogurt: 135-140 ℃/2-4s UHT sterilization, secondary sterilization after fermentation, loss of probiotics, long-term storage

4. Vaccination&Fermentation Section (Core of the Entire Production Line)
Equipment: Vertical insulated fermentation tank (with scraping wall stirring and interlayer temperature control)
1. After sterilization, cool to 42-43 ℃ (the optimal activity temperature for lactic acid bacteria)
2. Strain: Lactobacillus bulgaricus+Streptococcus thermophilus, inoculated at a ratio of 1% -4%
3. Stirring type: Closed and constant temperature fermentation in a tank for 2.5-4 hours; online monitoring of pH, stopping fermentation when pH drops to 4.2-4.6
4. Quickly cool to 18-22 ℃, gently stir at low speed to break the curd, and avoid layering and draining the yogurt
>Solidification type: After filling and sealing, it is sent to a constant temperature fermentation tunnel/fermentation room for 42 ℃ insulation fermentation

5. Post processing (flavor blending)
Equipment: Fruit granule adding machine, static mixer, buffer storage tank
When making strawberry, peach and other flavored yogurt, add jam/fruit pulp particles in a quantitative amount online after fermentation and cooling, gently mix without breaking the fruit particles.

6. Filling and packaging section
Match different filling machines according to packaging form:
-Cup yogurt: fully automatic plastic cup forming, filling and sealing machine
-Bottled yogurt: rotary liquid filling machine
-Bagged yogurt: aseptic bag filling machine
-Room temperature brick packaging: Tetra Pak aseptic filling machine
After filling, spray code, label, pack, and send to the cold storage

7. CIP fully automatic cleaning system (essential for dairy products)
Independent acid-base cleaning circuit, no need for manual disassembly of pipes; After production, the tank body, pipeline, homogenizer, and filling machine are automatically cleaned and disinfected in situ to ensure food safety and meet food SC production standards

3、 Classification of Capacity Specifications
1. Small milk bar line: 0.2-1 tons/day, batch type, suitable for stores and small ranches
2. Medium sized factory line: 2-10 tons/hour, semi-automatic continuous, small and medium-sized dairy plants
3. Large scale industrial production line: 10-50 tons/hour, fully automated closed-loop control, complete turnkey project

4、 Key process control points
1. The inoculation temperature must not exceed 45 ℃, as high temperatures can directly kill lactic acid bacteria and result in fermentation failure
2. The fermentation endpoint is strictly controlled by pH, and excessive fermentation results in a sour and astringent taste
3. The speed of emulsion breaking and stirring should not be too high, and the shear force should not be too strong. The yogurt will become thinner and produce water