Arefrigerator is one of the most important pieces of equipment in the kitchen for keeping foods safe. These electric units are so commonplace today, we forget a refrigerator was once little more than a box with a block of ice used to supply a rather undependable source of cold air. But we are instantly reminded of its importance to our daily lives when the power goes off or the unit fails, putting our food’s safety in jeopardy.
History of Refrigeration
In prehistoric times, man found that his game would last longer if stored in the coolness of a cave or packed in snow. He realized the cold
temperatures would keep game for times when food was not available. Later, ice was harvested in the winter to be used in the summer. As man
became more industrialized and mechanized, ice was harvested from lakes and rivers or manufactured, stored, and transported to many countries. Even today, ice is still manufactured for this purpose.
The intermediate stage in the history of cooling foods was to add chemicals like sodium nitrate or potassium nitrate to water causing the
temperature to fall. Cooling wine via this method was recorded in 1550, as were the words “to refrigerate.” The evolution to mechanical refrigeration, a compressor with refrigerant, was a long, slow process and was introduced in the last quarter of the 19th century. The science of refrigeration continues to evolve. In 1996, there was a change made in the type of refrigerant used to comply with the Regulatory Clean Air Act, Title 6. The old refrigerant known to most people as “freon,” a tradename, was replaced with HFC 134a, a new refrigerant less injurious to the ozone and still just as effective in keeping food cold.
As consumers, we should notice no difference.
