Among the challenges facing many food manufacturers is how to apply heat technology in a way that destroys harmful bacteria without damaging taste, texture and important nutrients. This is particularly essential for sensitive products such as baby formula, whey protein concentrates, liquid egg and processed cheese.
A technology developed by APV®, helps manufacturers of these products achieve just the right amount of heat.
It's All About Timing
The APV Instant Infusion Gold System™ involves preheating milk concentrate to 55°C using a plate heat exchanger, followed by almost instantaneous heating to a heat treatment temperature of up to 148°C using steam infusion.
In the form of thin strings, the product passes into a chamber heated by direct steam. The ratio of heating medium to product is exceptionally high. This means that there is a high surface ratio of product to steam.
The high surface ratio enables the temperature difference between product and heating medium to be kept to a minimum, usually less than 1°C, thus eliminating the partial overheating of product that occurs in all other forms of heat treatment and especially steam injection.
Smart Design Creates Smarter Process
The bottom cone of the chamber is cooled using a water jacket to create a thin film of condensate on the wall of the infuser. This reduces the formation of deposits as the hot milk strings hit the bottom of the vessel.
The product is then held at the required heat treatment temperature, not in a normal holding tube, but in a self-cleaning holding cell that eliminates the excessive deposit formation that would normally form in a holding tube.
From the exit of the holding cell, the product passes to a flash vessel under vacuum where it is instantly cooled to approximately 48°C. The product is then cooled further before being routed to the spray drier.
Better Process, Better Product
The result is a process that brings a number of benefits, including uniform bacterial kill rate for medium and high viscosity products, consistent product quality, less fouling and proven long operating times.
The technology is currently in use by manufacturers of infant formula milk and milk concentrates in locations as diverse as the Czech Republic, Vietnam, Denmark, Germany, Switzerland and the United Kingdom.