SNOW FORMATION IN IQF FREEZERS
Snow formation in IQF freezers is one of the most overlooked cost and it represents more loss for the processors annually, than their capital cost and power consumption all together.
The question is why is there any snow formation at all, and how can we minimize the effects it has on the overall production?
Snow formation inside IQF tunnel freezers is tightly connected with the subject of dehydration. As we mentioned in our previous article about “Dehydration during freezing and why you shouldn’t ignore it”, dehydration is the process of water loss through the product’s membrane when it is exposed to cold air flow during freezing.
When dehydration occurs, there will be a loss of weight of the product. The humidity that moves from the product into the air will saturate the air, and there is a maximum of how much moisture the air can take. When the air is 100% saturated, there will be snow created. This phenomenon is called precipitation and it is the same as when rain or snow is created out in the atmosphere.
The main reason for the occurrence of precipitation inside an IQF freezer is the large amount of warm and mostly wet product that enters the cold environment inside the freezer. After precipitation the air will no longer be saturated and more moisture can be sublimated from the product to the air, thus more loss of weight of the product inside the IQF tunnel freezer.
We have already established that the snow formation inside the IQF tunnel freezer is an indicator of product loss and dehydration. What can we do to avoid dehydration then?
In order to minimize dehydration you need to avoid precipitation and thus sublimation, have better aerodynamics (less disruption of the air flow) and better air speed.
Due to the temperature variations inside an IQF freezer, it is impossible to completely prevent snow formation, but the OctoFrost™ is built with numerous design features to minimize snow formation which in consequence increases the yield of your production.
The OctoFrost™ is adjusting the fans speed in order to have good air velocity and air pressure, thus it has great control over the aerodynamics inside the OctoFrost IQF freezer. The humidity in the air inside the OctoFrost stays constant and does not precipitate in snow, therefore the product dehydration is kept under 0,1% - 1%.
The fact is that the snow building up inside your freezer is product loss, and that is because an IQF freezer is a closed system and the humidity creating the precipitation doesn’t have anywhere else to come from than from the products you are freezing.