Extracting heat in next to no time
So what is this impingement all about? Pressurised liquid nitrogen, with a temperature of -196°C, is sprayed onto the product at high velocity to freeze it immediately. This way, the CWI can extract heat faster. Increasing the nitrogen’s speed is effective: It permeates the food items’ thermal resistance and creates an ice crust around them – locking in natural flavours, nutrients, and moisture. With cryogen impingement, you have five to ten times less dehydration than with conventional freezers. By limiting weight loss, the CWI significantly improves product yield. These flash-freeze effects provide prime IQF quality, something that cannot be achieved with mechanical freezers that operate at -40°C.
A high-velocity air stream
Due to the rapid heat exchange inside the freezer, most of the nitrogen instantly turns into gas. A set of jet-like blower wheels powerfully moves the nitrogen through the tunnel, creating a high-speed gas flow. Impingement plates help increase the static pressure and the overall airstream velocity. You can have the gas move at 20-30 metres per second – but you still stay in full control, depending on your product. While poultry and potatoes may be cooled with such power, lower speeds should be used for peas and berries to prevent them being blown away. A key side effect: The blower-wheels help avoid blind spots where nitrogen deposits can form piles of snow and ice.
Whether it’s seafood, meat or vegetables that you’re freezing: The CRYOLINE® CWI makes sure it’s done in an efficient and effective way. And while your products inside the CWI move to its wavy beat, you’ll certainly have your finger on the pulse of quality freezing.