The modern history of frozen foods

The modern frozen foods technology was invented by Clarence Birdseye in early 1900-s, and it took about 50 years for the original idea to succeed in the marketplace. After World War II, complimentary inventions of affordable refrigerators and microwave ovens created an environment, in which frozen foods industry could develop and thrive.

[Clarence] Birdseye worked as a fur trapper and trader in the Canadian North, where he noticed that fish would freeze almost immediately after being caught, and when cooked later -- even weeks later -- these quick-frozen fish tasted much better than fish mechanically frozen in warmer climates.

Birdseye began his experiments with freezing in 1916, and eventually came to understand that if fish was frozen very, very quickly its cellular structure was damaged far less, so that when thawed it was nearly indistinguishable from fresh fish.
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Frozen foods went nationwide in 1944, when Birdseye suggested leasing insulated railroad cars for shipping. He further changed the grocery landscape by contracting with American Radiator Corporation to build display freezers, which General Foods then leased to stores. By the early 1950s, more than half of American grocery stores had a 'frozen food' section.