Blast Chillers and Blast Freezers are the perfect choice for caterers within every sector who cook and then chill food such as hospitals, pubs, airlines, schools, and event caterers. Historically Blast Chillers and freezers were previously seen as energy hungry units that were only suitable for large institutions – This has changed with units now available to offer easy, energy efficient blast chilling.
Blast Chillers come in a range of sizes from 10kg under counter units to modular roll in units able to handle up to 320kg of food. Typically reach-in blast chillers range in capacity from 10kg to 50kg whilst the modular units range from 90kg to 320kg.
Blast Chillers and Blast Freezers: key energy considerations
Food safety – the vital issue: HACCAP compliance is a must with blast chilling, so before buying a unit that uses less power ensure it’s able to chill food stuffs in an acceptable time. Regulations state that the core of the food must be chilled in 90 minutes and frozen in 240 minutes.
For added flexibility consider a unit that can chill from +90°C rather than the standard +70°C
The right size for the job: An easy way to reduce energy use in blast chilling is to have a unit designed to chill just the amount of food you need. If you are producing low volumes of food a small undercounter blast chiller will be more efficient.
Before you begin: Ensure that the blast chiller or freezer is switched on and is at the correct temperature (3°C for chilling / -18°C for freezing) before hot food is loaded, otherwise the refrigeration system will be overworked. As well as being less efficient to run there’s the risk that the cycle may not complete in time.
Half loads: When blast chilling or blast freezing less than a full load, space the trays out evenly throughout the cabinet. This will speed up the process and ensure the food is uniformly chilled. If possible, use a food probe to control the cycle, as this will save energy by stopping the cycle as soon as the correct temperature is reached.
Use a food probe: Using a food probe to control the blast chill cycle can save energy. To ensure the most accurate temperature readings, position the probe in the middle of the tray on the middle shelf, in the densest part of the food.
Air distribution: Having even, all round air flow not only ensures uniform chilling and minimises the risk of damaging the food but also reduces energy use.
Self-diagnostics: With any unit maintenance is key to ensuring your product runs efficiently for the life of the unit. Blast Chillers are available with self diagnostics, which mean service engineers can quickly find a fault and correct it. Maintenance reminders such as condenser cleaning lights are also invaluable in keeping your refrigeration running smoothly.
Keep it closed: Once the blast cycle has started, do not open the door, for example to add more trays of product. The food already in the unit will be subjected to warm air, while the food that is added won’t get the full blast cycle. This not only reduces the efficiency of the unit but, food safety will be compromised.
Don’t cover food: Don’t cover food in trays in the blast chiller or freezer, it will compromise the efficiency of the blast cycle. Modern blast chillers and freezers have special airflow designs, such as Williams’ AirSmart, which protect even delicate food, so there is no need to cover it.
High performance insulation: increased thermal efficiency can be achieved with improved insulation. By maintaining a constant temperature more easily, and reducing heat ingress the refrigeration unit will have to work less, therby reducing its energy use.
Storage Mode: Many blast chillers and freezers now come with a storage mode. The energy savings available for this can be sizeable as it negates the need for a separate unit to hold products at the appropriate temperature. This is especially true for high volume modular units.