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Food & Beverage
Boosting dairy processing with multi-stage plate heat exchangers
Milk bottling production line in a dairy plant. Photo: dreamstime. com
Multi-stage plate heat exchangers are transforming milk pasteurization by significantly improving energy efficiency, hygiene, and temperature control. Their compact design, high thermal performance, and ease of maintenance make them ideal for modern dairy processing. This article explores how they work and why they’ re critical for safe, sustainable milk production.
Text by HFM
Heat exchangers are widely used in the food and beverage industry, especially in processes such as heating, cooling, pasteurization, and disinfection. They regulate temperature, ensuring that physical and chemical reactions occur at optimal conditions while guaranteeing that the final product is safe for human consumption. Plate heat exchangers are one of the most widely used heat exchangers for the dairy industry, because the design of this equipment provides large heat transfer area, which significantly enhances the turbulence while improving the heat transfer performance. Furthermore, since plate heat exchangers can be easily assembled and disassembled, maintenance and cleaning processes are very practical, which is essential in industries that demand high hygiene standards. In the dairy industry, plate heat exchangers, specifically multi-stage one, are widely used in milk pasteurization, pre-cooling and cream separation, etc. It meets food-grade hygiene standards, such as EHEDG certification, which guarantees the safety and cleanliness of the processing. Because milk is a highly perishable product, pasteurization is essential to ensure the microbial safety of the product while not affecting its taste and nutritional value. This also requires attending to some of the strictest industrial standards and regulations. Effective pasteurization requires careful temperature management, and the use of plate heat exchangers can not only ensure the industrial standards but also increase the energy efficiency of during the production.
Basic principle of milk pasteurization Pasteurization is a process developed by French scientist Louis Pasteur. It is conducted for the conservation of food and extension of their shelf life. It consists of the sterilization of food by killing harmful bacteria present in it through a subtle change in temperatures. If properly done, pasteurization ensures the microbial safety of the food, destroying pathogens, such as Tuberculosis bacillus and Escherichia coli. For dairy industry, specifically, as important as the safety of the milk for consumption, the process also must preserve its nutritional profile. Early pasteurization methods often used direct steam injections or shell and tube heat exchangers. However, these traditional methods are characterized by low energy efficiency, unstable temperature control, large equipment
42 Heat Exchanger World July 2025 www. heat-exchanger-world. com