One of the biggest issues with blast chillers is that operators commonly underestimate these units’ complexity. Fortunately, with newer technology and control boards, these units have become easier to use than in the past. Still, chilling product in blast chillers is much different than simply placing food in a refrigeration unit. There needs to be an educational component for those working with this equipment about how food should be sized, shaped and packaged prior to the chilling process for optimum results and to ensure adherence to proper food safety protocol.
With blast chiller capacities ranging from 30 to 1,300 pounds, catering operators can choose the style and size that best fits their needs. When purchasing a blast chiller, operators can choose between undercounter units, countertop models that may include shelf space underneath or stand-alone systems. Roll-in and reach-in models are available, too. While reach-in blast chillers have permanent racks inside of the cabinet that can accommodate either hotel- or full-size sheet pans, roll-in units use mobile tray holders. Some models provide removable, adjustable shelving, which can provide added versatility. The majority of these units utilize 2-inch-deep pans that accommodate 10 pounds of product.
The ideal unit size will depend on the volume and application. Countertop blast chillers hold between 3 and 5 full-size pans, while roll-in units are geared for quantities of more than 200 pounds. One common mistake operators make is utilizing too big of a pan for blast chilling product. This can compromise the cooling process as the cold air won’t properly infiltrate the center of the pan. Proper container sizing plays an important role in ensuring quality results.
Also, when choosing a model, consider the type of product being chilled. For example, more delicate foods such as bakery items, rice and vegetables require a more controlled chilling method than heartier, denser food, like meat. Some blast-chilling units offer both hard and soft chill capabilities. With a hard chill, temperatures come down more quickly and bring food to an almost frozen state. Soft chill units bring product temperatures down to less than 40 degrees F gradually, making the process a little less harsh than a hard chill.
For operations with varying production levels, blast chillers that provide two independent cooling compartments can provide additional flexibility. These units can accommodate smaller amounts of food in a single compartment without cooling the entire interior, which can enhance efficiency.
This equipment utilizes large compressors, and operators can decide if a self-contained or remote condensing unit works best. Although some blast chillers require drain connections, catering operations may find a model with built-in defrost capabilities, which eliminates condensation on condenser coils, works best.
Features vary by model and may include stainless-steel interiors and exteriors, 4-inch-thick panels with CFC-free polyurethane foamed-in-place insulation, a remote refrigeration system sized to match the specific application, a door gasket heater that prevents doors from icing over, and a surface exterior-mounted control system with a digital readout of interior ambient temperature and probe temperatures, as well as automatic defrost and hold cycles.
Innovations include touch-screen controllers that can time different products, self-correcting evaporator fan motors and carbon graphite blades that change pitch to improve airflow in the event evaporator coils frost up.
The monitoring technology with these units has improved greatly in recent years. For example, in the past, operators would use handheld thermometers and a written log to track the temperature of food being blast chilled. With today’s more sophisticated technology, the majority of these units now offer data recording capabilities for HACCP documentation, with models using different methods to accomplish this.
Most blast chillers utilize a printer that records information on paper, while others have either a data port to upload reports to a computer or a USB drive for downloading temperature details on a portable storage device. Each method offers both pros and cons. For example, operators who choose a unit that prints HACCP data will need to purchase paper and designate a storage area to file these documents. Blast chillers that connect to computers may require special cables or access to hookup lines.