Long ago our ancestors spent the winter harvesting ice to store in insulated caves so they would have ice all year round. During the warm months, they used this stored ice to preserve their food. This ice-block method of refrigeration was still being used at the beginning of the 20th century! Refrigeration has certainly come a long way in the past one hundred years, allowing commercial refrigeration to provide a variety of fruits and vegetables year-round.
Think of all the varieties that are utilized today: transporting food from one country to another, keeping food fresh in restaurants and supermarkets, allowing foods to last much longer than if they were kept at room temperature, and bringing us a variety of foods that we’d otherwise be unable to eat since they wouldn’t survive the trip to the USA!
The Process of Cyclic Refrigeration
Within the refrigerator are three parts crucial to the process of cyclic refrigeration. A compressor is used to apply pressure to the gas inside the refrigerator. As the pressure builds coils or heat-exchanging pipes allow the heat to dissipate and the gas turns back into a liquid. An expansion valve allows the liquid to travel back toward the compressor and begin the process over again.
Cyclic refrigeration allows the chamber inside the refrigerator to remain cold all the time, no matter how hot it may be in your house. By using a refrigerant, a liquid that boils at an extremely low temperature (usually a mixture of ammonia which boils at -27 degrees F), the refrigerator box is surrounded and filled with air that’s been cooled by the evaporation of the boiling liquid.
Types of Commercial Refrigeration
Supermarkets are constantly in need of huge refrigerators to store foods like meat, dairy, and some fruits and vegetables. Many times supermarkets utilize display refrigerators that have no door. These refrigerators make it easy for customers to select products and load up their cart.
Restaurants, churches, schools, and other large organizations often purchase huge refrigerators for their kitchens or cafeteria areas. Most of the time, these refrigerators look much the same as a homeowner’s refrigerator, but are two or three times bigger.
Some of today’s homeowners are choosing commercial refrigeration options for their home. These larger units offer lots of storage space but take up about two times the amount of space that a regular refrigerator would need. One style that’s becoming popular is the reach in refrigerator unit. This option features two glass doors, which slide back and forth instead of doors that swing open.
Sometimes food needs to be cooled incredibly fast in order to keep it fresh and avoid food poisoning situations. In these cases commercial refrigeration known as blast chillers are used. A blast chiller can drop the temperature of food from 21 degrees Celsius to -16 degrees Celsius in about an hour and a half. rv fridge