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Refrigerators are a relatively new invention, with early methods of cooling food including placing it in cold streams or underground cellars. The first kitchen appliance resembling a refrigerator was the icebox, developed just before the 19th century. Refrigeration technology improved over time, with the first refrigerator being developed in 1876 by Carl von Linde. Environmental concerns led to the removal of harmful chemicals like CFCs, and modern refrigerators have added features like automatic defrost and ice-making components.
Today in the United States approximately 99.5% of households own a refrigerator. The idea of keeping food fresh to prevent spoilage isn’t new, but it can be surprising to realize that the appliance, a fixture in most homes, is relatively new to the world.
In the past there were different ways to keep food fresh and humans used a diverse number of natural environments. Placing food in cold streams, secreting it in the back of caves, or digging underground to create cellars were all early methods of cooling foods. People also cut ice in the winter and stored it in deep cellars or iceboxes. Such ice could be preserved for a significant amount of time, especially if covered with salt.
The first kitchen “appliance” that somehow resembles the refrigerator is the icebox. These were developed just before the 19th century. They were simply wooden boxes, often set up in a house, and sometimes lined with metal or other materials. People bought ice, put it in the box, and then stored the foods that needed to be kept cool. Ice would melt slowly, so most iceboxes had drip trays, which could be removed and emptied.
Many studies on aspects of refrigeration were developed before the icebox, but they simply hadn’t been put into practice yet. Dr. William Cullen is often considered a pioneer in refrigeration technology as scientific experiments by him in the early 18th century observed how liquids evaporated in a vacuum-like environment. Other scientists decided to study aspects of cooling and chemicals. Dr. John Goorie created an ice-making machine to help meet the needs of yellow fever patients, and Michael Faraday researched the properties of ammonia. Faraday realized that ammonia had a cooling effect.
These early studies, and the ideas of many other scientists, led to the development of the first refrigerator in 1876 by German engineer Carl von Linde. He had devised a process by which large quantities of liquids could be converted into gases to keep a defined environment cool. Linde continued to perfect his invention, and others followed suit. By 1920, over 200 companies were producing different models and, at the same time, many companies had developed technologies to produce them with combination freezers. They were still top-of-the-range appliances, and many people continued to use the old icebox stand instead.
In the decades since, refrigeration technology has improved, but some of the chemicals used to create a cold environment have caused problems. For example, Freon® has often been used to cool or freeze foods. While this may have been effective, it released chlorofluorocarbons (CFCs), which were later found to be dangerous to the environment. Also, early appliances used significantly more electricity than their modern counterparts. Efforts on behalf of conservationists and environmentalists were ultimately successful, and by the 1980s most models ran on less energy and didn’t use or release CFCs.
Along the way, other features have been added to refrigerators, and bonuses have been added to automatic defrost capabilities and ice-making components. The cost has also become more affordable for most families, although there are still luxury models that are well outside the price range of the average middle-class family. Basic refrigerators can now be had for about half their 1920s retail prices.
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