In 1929, what did Clarence Birdseye introduce?

In 1929, Clarence Birdseye introduced frozen foods to the American public through his quick-freezing process.

Birdseye’s breakthrough grew from observations he made while working as a fur trader in Labrador. Fish caught in extremely cold conditions froze almost immediately, and when thawed months later, they retained much more of their original taste and texture than food frozen slowly. He realized that speed was the crucial factor because rapid freezing creates smaller ice crystals and causes less damage to food’s cells.

Birdseye developed commercial freezing equipment, founded Birdseye Seafoods in 1924, and helped turn flash-frozen fish, meat, fruits, and vegetables into products that could be sold widely. In 1929, his company and patents were acquired by Postum, later General Foods, which invested in distribution and refrigerated retail equipment.

The answer is sometimes phrased as “flash freezing” or “quick freezing.” Those describe the technology Birdseye pioneered; “frozen foods” describes the consumer product he introduced. Both refer to the same innovation, making Frozen Foods the fair canonical answer to this question.