Milk Powder Manufacturing Process Step by Step
Infant formula production is one of the most technically demanding areas in food engineering. For many buyers and manufacturers, the core concerns are not production capacity, but rather: Is the process complex? How can contamination be avoided? How can energy consumption be controlled? And which step is the key to determining the quality of the infant formula?
This article will break down the milk powder production process step by step, revealing the quality control logic behind each step, and introducing how to optimize the entire production process through professional equipment.
Raw milk reception and storage
The starting point for milk powder production lies in the control of raw materials. This stage directly addresses the issue of raw milk contamination, which is the biggest concern for customers.
Receiving inspection: Each batch of raw milk must undergo strict physicochemical and microbiological testing before entering the facility to ensure that it is free of antibiotics and impurities.
Filtration and milk purification: Physical impurities such as cow dung and hair are removed using a centrifugal milk purifier.
Cooling storage: Raw milk is temporarily stored in milk storage tanks at a temperature below 4°C to inhibit bacterial growth and prevent rancidity.
Addressing user pain points: An effective receiving process can prevent contamination at the source, laying the foundation for subsequent food safety.
The role of ster
ilization process in milk powder production
Food safety is the lifeline of milk powder production. The pasteurization process is the core barrier to kill pathogenic bacteria and ensure consumer health.
Low-temperature long-time sterilization (LTLT): 63-65°C for 30 minutes, rarely used in large-scale industrial production.
High Temperature Short Time Sterilization (HTST): Maintaining 72-75°C for 15-30 seconds is the mainstream choice, balancing safety and nutrient retention.
Ultra-high temperature instantaneous sterilization (UHT): 120-140°C for several seconds, for special formulation needs.
Key takeaway: Incomplete sterilization will directly lead to excessive microbial levels in the finished product; excessive sterilization will damage protein activity. Precise temperature control is crucial.
Evaporation system and concentration
The main task of the evaporation system is to concentrate milk with a solids content of about 13% to 45%-52% concentrated milk. This step is directly related to energy consumption—evaporating water requires a large amount of heat energy, usually accounting for 30%-40% of the total energy consumption of the plant.
How to reduce energy consumption?
A modern solution is to use multi-effect evaporators and mechanical vapor recompression (MVR) technology.
Traditional multi-effect evaporation: The secondary steam generated by the previous effect is used to heat the next effect, which significantly reduces the amount of fresh steam used.
MVR technology: The evaporated steam is recovered, heated and pressurized by a compressor, and then recycled, reducing energy consumption by more than 60%.
In this aspect, Weishu Milk Machinery’s energy-efficient evaporators, through optimized heat recovery design and MVR technology, can help customers significantly reduce operating costs while ensuring uniform and stable concentrated milk.
Detailed Explanation of Spray Drying Technology
Spray drying is the most crucial piece of equipment in the entire milk powder production line, determining the solubility, particle structure, and moisture content of the milk powder.
Working principle:
Concentrated milk is injected into the hot air at the top of the drying tower via a high-pressure pump or centrifugal atomizer, forming fine droplets. The droplets evaporate their moisture upon contact with the hot air (0.2-0.4 seconds), forming dry powder particles.
Why is it the most important?
Directly determines instant solubility: particle size and surface structure are determined at this stage.
Impact on the retention of heat-sensitive nutrients: Despite the high temperature, the contact time is extremely short, resulting in minimal loss of vitamins and other nutrients.
Controlling final moisture content: The moisture content of milk powder leaving the tower should be controlled between 2% and 4%. Too low a moisture content will affect solubility, while too high a moisture content will easily cause clumping.
Milk powder cooling and packaging
Milk powder fresh from the drying tower is at a high temperature (60-70°C) and may absorb moisture from the air. Therefore, cooling and packaging are the last line of defense to ensure shelf life.
Fluidized bed cooling: The dried milk powder enters the fluidized bed and is rapidly cooled to below 30°C by cold air to prevent thermal denaturation.
Screening and magnetic separation: Remove any clumps or metallic foreign objects that may be present.
Automated packaging: Nitrogen-filled or vacuum-packed packaging is performed in a low-humidity, positive-pressure clean environment.
Future Links: To address the need for large-scale automated packaging, we will expand on the collaborative design and efficiency optimization of packaging machine clusters in future articles.
Common Production Challenges
In actual production, even with a reasonable process design, some typical problems will still be encountered. We deliberately “bury” these problems here as a starting point for future troubleshooting:
Adhesion to the walls: Milk powder particles deposit on the inner wall of the drying tower, and prolonged high temperature causes scorching. This is usually caused by poor atomization or uneven hot air distribution.
Excessive moisture content: The finished granules contain more than 5% moisture, leading to clumping and mold growth. This is related to improper drying temperature or exhaust volume settings.
Inconsistent milk powder quality, including poor solubility and inconsistent color, often stems from concentration fluctuations during the concentration process or unstable spray pressure.
How Weishu Milk Machinery optimizes the entire production process
Faced with the aforementioned complex processes and potential challenges, relying solely on general-purpose equipment often fails to balance quality and cost. Weishu Milk Machinery offers more than just individual machines; it provides a complete plant optimization solution:
Integrated process design: From raw milk receiving to packaging, the entire process complies with GMP and HACCP standards, eliminating cross-contamination.
Energy Management System: Through MVR energy-saving evaporators and waste heat recovery spray drying towers, we help customers reduce overall energy consumption by more than 30%.
Intelligent control: The PLC fully automatic control system monitors temperature, pressure, and concentration in real time to ensure the consistency of each batch of milk powder.
Targeted solution to wall adhesion: A combination of cyclone separator and bag filter is adopted, and the hot air angle of the tower is optimized to effectively reduce the rate of coke powder adhering to the wall.
Summarize:
Although the milk powder production process is interconnected, as long as we grasp the three core elements of “sterilization to ensure safety, evaporation to reduce energy consumption, and drying to determine quality,” and with the help of Weishu Milk Machinery‘s professional design and energy-saving technology, we can achieve efficient and low-cost large-scale production while ensuring food safety.
