Freezing Before the Freezer
People in cold climates have always frozen food outdoors, and fish and game kept hard in winter. Artificial refrigeration in the nineteenth century made it possible to freeze food at any time of year. By the 1870s and 1880s, experimental shipments of frozen meat were crossing oceans from Australia, New Zealand and South America to Britain, helping establish the frozen meat trade. This early frozen meat was generally frozen slowly, often in cold rooms or chilled by brine, and could be watery and less appealing once thawed.
Why Speed Matters
The difference between slow and quick freezing is largely about ice crystals. When food freezes slowly, water inside cells tends to form relatively large crystals, which can damage cell walls. On thawing, the food may lose juice and turn soft or mushy. Faster freezing tends to produce smaller crystals, and the food generally keeps its texture better. The idea was understood in broad terms in the early twentieth century, though the full details of freezing physics were worked out later.
The Birdseye Story
The American Clarence Birdseye is the name most often tied to quick freezing. According to the usual account, he saw Inuit people in Labrador fishing through the ice in the 1910s and noticed that fish froze almost instantly in the bitter air and tasted fresh when cooked months later. Back in the United States he experimented with freezing food rapidly between cold metal plates and, in the 1920s, founded a company in Massachusetts to freeze fish and other foods.
The anecdote is widely repeated, but details are hard to confirm, and others had also worked on quick freezing and fish freezing in earlier decades. Birdseye’s contribution is better described as developing a commercial process and packaging, and building a business around it, than as discovering that quick freezing works. In 1929 his business was sold to a larger food company, and a test marketing of frozen packages began in a few stores around 1930.
Getting Frozen Food to Customers
Selling frozen food required a chain of cold storage, from factory to freezer truck to rail car to store. That chain was expensive to build, and early grocers needed special display cabinets. For years frozen food sold slowly, in part because few homes had anywhere to keep it for more than a day or two. Frozen foods were also priced above fresh and canned ones.
The expansion of refrigerated shipping helped, as did the growing number of household refrigerators with small freezer compartments. Wartime rationing of canned goods in the United States during the Second World War pushed some shoppers to try frozen vegetables, and the postwar period saw sales climb quickly.
Supermarkets and Home Freezers
After the war, supermarket chains installed open and upright freezer cases, and frozen peas, orange juice concentrate, fish sticks and prepared meals became staples. The frozen dinner on a compartment tray, popularly dated to the early 1950s in the United States, joined an expanding market for convenience foods. Home chest and upright freezers sold in large numbers in the 1950s and 1960s, particularly in suburban and rural households that bought meat or garden produce in bulk.
Microwave ovens added to the appeal in later decades, since they let people thaw and heat a frozen meal in minutes.
Later Developments
Industrial methods vary. Plate freezers, blast freezers, and tunnels with cold air or liquid nitrogen are used for different products. Individually quick frozen items, such as loose peas or berries, flow freely out of a bag. Better packaging and tighter temperature control have helped limit freezer burn, a surface drying of frozen food.
Frozen food has detractors as well as admirers. Some critics find it blander than fresh food, and some concerns have focused on salt, fat and heavy processing in prepared meals. Plain frozen vegetables and fish are generally regarded as comparable in nutrition to fresh produce that has been stored for several days, though results depend on the product. This article is a history, not dietary advice.