The best processing results are achieved through co-creation of production lines with customers. This close partnership encourages the sharing of expertise and specialist knowledge; gives clear understanding of expected key performance indicators (KPIs), drives project efficiency, and offers the potential to exceed system performance expectations. The result is that everyone wins—the food manufacturer, the technology provider, and the consumer.
Infant formula or other powder-based early life nutrition (including baby milk, follow on milk, and growing up milk) requires the strictest food safety and quality standards. To meet the demands of this market place, producers want absolute certainty in hygiene and food safety while protecting the nutritional value of the product. Other factors that impact powder quality classification include the level of scorched particles, solubility index, color, structure, and other functional parameters. These are important considerations in the design of a processing line and the final value of the infant formula.
Infant Formula Processing
There are many stages in a complete process line for producing infant formula and consideration needs to be taken for the type of ingredients, their quality, and their application (liquid, powder in wet or dry compounding). Each stage requires careful design to ensure the highest quality and food safety are maintained and that the plant is efficient, flexible, and reliable.
Mixing. The first main step in producing infant formula is mixing. The quality of mixing has a big impact on end product quality and, where solids and liquids need to be combined, good dispersion is essential. To optimize quality and hygiene, it’s recommended to use a vacuum mixer.
There are many production benefits to a closed vacuum mixer including reduced mixing time, greater energy efficiency, reduced waste and easy maintenance; but for the purposes of this article let’s look at quality and safety issues it addresses.
During vacuum mixing, powder is sucked in from a closed powder hopper or bag system. Using the vacuum level in the tank, the powder is washed out directly into the circulating liquid below the liquid surface; ensuring dust is not released into the surrounding atmosphere. The wet and dry phases of the process are thereby completely separated, reducing the risk of bacteria formation. A vacuum prevents air from entering the mixture, reducing undesirable effects such as oxidation, nutritional degradation, and discoloring. The high shear pump is located at the side of the mixer, which gives added ergonomic benefits including easy access and a safe environment for maintenance.
Evaporation. The next main stage in the infant formula manufacturing process is an evaporation stage, which is an energy efficient method of increasing total solids of the formula. An evaporator works by adding heat to the solution to a point where liquids turn into vapor and can be separated. The type of evaporator selected will depend upon local energy costs. Mechanical vapor recompression evaporators use a mechanical compressor or fan to compress the vapor and need ample electricity supply. Thermal vapor recompression systems use steam jets for compression and require a ready supply of steam to be available. The cost of steam versus the cost of electricity is, therefore, one of the primary considerations in selecting an evaporator for a particular plant.
The evaporator temperature is related to the evaporation pressure. System parameters are adjusted to optimize for product concentration and product quality as well as energy efficiency. Some plants select to use two evaporators which enable continuous production as one line is cleaned, the other is in operation; facilitating 24/7 production.
Using an evaporator reduces the energy required for spray drying and also helps extend the shelf life of the final product by removing occluded air from the fluid.