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Why do we need refrigeration?
Let's look at a time line illustrating how the modern refrigerator was developed and see if you can identify why people chose mechanical refrigeration to preserve their food.
In the beginning
What ways did people preserve food before the refrigerator was developed? Methods available for preserving food for people living in temperate climates were limited to things such as drying in the sun or wind (for berries, fruit, vegetables and meat), using salt (for meat). This changed the taste and texture of the food considerably and limited the range of food available. Preserving food by lowering the temperature - either chilling or freezing - is able to extend the time over which the food items can be used and can provide a higher quality of product.
1660
In the UK 'Ice Houses' were used to store ice, which was used for preserving things such as food. The ice was cut in winter or imported from colder countries such as Norway by the shipload. Transportation costs made this expensive.
1755
William Cullen, in his laboratory in Glasgow University, was one of the first scientists to develop a scientific means to produce ice.
1835
Jacob Perkins patented a closed circuit machine to produce the cooling or freezing of fluids. Artificial ice-making began to be more widespread and the price and quality of the product meant that ice became much more widely used as a means of preserving foods such as fish. But it was hard to keep up with demand.
1850s
Mechanical refrigeration began to take off. Industrialists were able to acquire refrigerating machines, which could cool or freeze items more cheaply and more easily.
early 1900s
The manufacture of domestic and small commercial refrigerators (which could be used in shops) began to take off, particularly in the USA.
1950s
Refrigerators started to become affordable for most households in the UK. And nowadays most kitchens will have both a refrigerator and a freezer.