UHT Treatment. Heat treatment technology like SPX FLOW Instant Infusion is used for the production of infant formula because it provides food safety nutritional quality protection. The process is a gentle form of heat treatment that involves preheating to 75 degrees to 85 degrees Celsius using plate and tube heat exchangers followed by rapid super-heating to around 140 degrees Celsius using steam infusion. The product is distributed in the form of thin strings into a chamber and is instantly heated by direct steam.
A short, accurate holding time in the range of 0.1 to 0.5 seconds avoids damage of essential amino acids, proteins, and vitamins that can result in nutritional degradation, unacceptable flavor changes, and the formation of burnt particles. The high temperature gives exceptional kill rate and eliminates even heat-resistant bacteria spores.
Optional Cavitation. A rotor with machined cavities spinning in a liquid chamber that generates controlled cavitation. The process increases spray drying efficiency by reducing fluid viscosity and enabling an increase in solids level as well as adding microstructural conditioning that optimizes particle structure, size, and distribution of solid components.
Combined High Pressure Pumping and Homogenization. Homogenizers are not complicated pieces of equipment but correctly designing and applying them requires skill and understanding. Homogenization helps with controlling final product quality, especially the levels of free fat which effect stability of the infant formula. Homogenizers act as a high pressure pump feeding the product to the spray dryer.
Spray Drying. The main part of the latter processing stages for infant formula production involves a spray dryer. This process is vital to final product quality and gives complete control over characteristics such as density, moisture content, powder properties, and sensorial aspects. As there is no further heat treatment, it is imperative that product contamination is not allowed. To this end, the air supply to the dryer uses HEPA filters and systems are designed for straight-forward cleaning, to minimize the risk of cross-contamination and to maintain food safety.
For example, SPX Flow’s Anhydro Triple A spray dryer incorporates an internal fluid bed. This supports the formation of strong powder agglomerates before entering the external fluid bed that further dries and cools the formula ready for packing. This efficient cooling of powder helps maintain quality during storage.
Both internal and external fluid beds in the drying stages of the process are self-emptying. This helps minimize contamination at product changeover, reduces loss of powder in the system, and also ensures powder is out of the system for a more effective clean-in-place cycle.
During spray drying the very fine powder and air is transferred to cyclones for separation. The powder fines can be returned to various positions in the process via a flexible fines return system that can further improve agglomeration.
Drying of infant formula powders also presents an explosion risk and comprehensive safety equipment is required to ensure protection of plant and personnel. Rupture chambers, vent ducts, firefighting systems, carbon monoxide detection systems, and suppression systems are all included in the design of a spray dryer.
Automation Systems. Another important part of an infant formula processing line is automation. Modern systems help ensure reliability and optimized operating costs but they also add flexibility, traceability, assist with the control of quality, and enhance overall operational safety of the system. Full integration with enterprise resource planning systems accurately measures performance and provides real-time data to monitor product quality and need for proactive maintenance to keep the system running reliably and consistently.
The production of powder-based nutrition involves many process stages, all which require careful integration and design to ensure the desired product quality and maximum food safety is achieved. To ensure all KPIs are met and high consumer confidence in a product brand, a close working relationship between processing companies and technology providers has been shown to yield the best results—offering efficiency, consistent quality, and assured food safety at every stage of the processing line.