Refrigeration in Dairies: Milk and Dairy Product Quality
The dairy industry is extremely temperature-sensitive. From raw milk reception to final product dispatch, each stage requires precise thermal control to ensure quality, safety, and compliance with USDA regulations.
The Cold Chain in Dairies
Milk is a highly perishable product. For every hour at an inadequate temperature, bacterial count can double, compromising product quality and safety.
Critical temperatures in the dairy chain:
| Stage | Temperature | Tolerance |
|---|---|---|
| Milk Reception | ≤7°C | Critical |
| Pasteurization | 72°C to 75°C | ±0.5°C |
| Post-Pasteurization Cooling | ≤4°C | Within 2h |
| Milk Storage | 2°C to 4°C | ±1°C |
| Cheese Ripening | 10°C to 14°C | ±1°C |
| Shipping Chamber | 2°C to 8°C | Per product |
Processes Dependent on Refrigeration
Raw Milk Cooling
Milk must be cooled to less than 4°C within 2 hours after milking. Direct expansion tanks or chilled water systems are used in this stage.
Pasteurization and Cooling
After pasteurization at 72-75°C, milk must be rapidly cooled to less than 4°C. Plate heat exchangers with chilled water are the most efficient solution.
Cheese Production
Different types of cheeses require specific ripening temperatures:
- Fresh cheeses: 2°C to 5°C
- Semi-hard cheeses: 10°C to 12°C
- Hard cheeses: 12°C to 14°C
Yogurt Production
The fermentation process occurs at 42-45°C, followed by rapid cooling to stop fermentation at the ideal point.
Helioterm Solutions for Dairies
Process Chillers
- Post-pasteurization milk cooling
- Chilled water for production tanks
- Production room air conditioning
Condensing Units
- Ripening chambers
- Storage chambers
- Rapid cooling tunnels
Success Case: Dairy in Minas Gerais
A medium-sized dairy in Minas Gerais processed 50,000 liters/day and faced problems with product quality and shelf life.
Identified Problems:
- Post-pasteurization cooling time of 4 hours
- Temperature variation in chambers of ±3°C
- Pasteurized milk shelf life of 5 days
- High energy consumption
Implemented Solution:
- 2 Helioterm 30 TR Chillers for process
- Correctly sized plate heat exchanger
- Chamber automation with PID control
- Remote monitoring system
Results:
- Cooling time reduced to 45 minutes
- Temperature variation of ±0.5°C
- Milk shelf life increased to 7 days (40% improvement)
- Energy savings of 28%
- Reduction of quality losses by 60%
Regulatory Compliance
Refrigeration systems for dairies must comply with:
- USDA regulations (equivalent to MAPA in Brazil)
- Food Safety Modernization Act (FSMA)
- Local and state health department regulations
Helioterm provides complete documentation for audits and certifications.
Conclusion
Adequate refrigeration in dairies is an investment in quality, safety, and competitiveness. Well-designed systems reduce losses, increase product shelf life, and ensure regulatory compliance.
Helioterm serves dairies of all sizes, from small artisanal cheese factories to large dairy industries.