April 14, 2017
When cooling food, it is extremely important to move the heat energy away from the food as quickly as possible. So it stands to reason the faster the air is moving, the faster the product will be cooled, right? From a basic level this is correct but a better way to rate performance is type of airflow employed and heat exchange efficiency during the cooling process. For the purpose of this post, let’s focus on airflow.
Pop quiz – how many sides are there to a standard foodservice pan? Some say four but actually there are six sides to a pan, front and back, right and left, then top and bottom. It is important to remember that you have six opportunities to remove heat energy from the pan and the top and bottom have the most surface area for energy removal.
There are two types of airflow normally seen in blast chillers:
- Turbulent air circulation which causes chaotic changes in air direction and speed
- Laminar flow provides layered air flow in a more orderly fashion to remove heat energy from the food and the cabinet
When blast chillers use turbulent air movement, there is a chance that not all of the air is circulated within the cavity to the coil and air flow is restricted between pans. Remember the pop quiz? Since the surface of the top and bottom of the pans are the largest areas for energy transfer and airflow is restricted, cooling cycles are extended significantly. Generally you find turbulent airflow in chillers that blow cold air over the products. Direct blowing, cold air can cause surface drying which leads to product waste.
With laminar flow, air is pulled across all six sides of the pan then directly through the coils extracting all of the heat energy possible on each pass. This means that even between pans, laminar air flow aids cooling also allows operators to chill products in 2” pans with lids. Lids help to reduce loss of moisture, flavor transfer and minimized edge freezing of products.
All Randell blast chillers employ laminar cooling technology and are available in a variety of sizes ranging from 3 pan, 5 pan and 18 pan upright models.
Check back in on the UB Retail Blog and more about blast chillers or another interesting topic.
Click the link http://www.unifiedbrands.net/products/randell/blast-chillers/ to find out more about Randell blast chillers