The juice squeezed from raw fruit is marketed today mostly as juice concentrate. Even canned and bottled ready-to-drink fruit juice is usually reconstituted from concentrate. Gail Borden experimented with producing juice concentrates after the Civil War. However, these products were not commercially successful until just after World War II, when frozen concentrated orange juice was developed. A group of citrus growers in Lake Wales, Florida, experimented with alternatives to canned juice, which didn't taste fresh. They developed a method of evaporating most of the water from fresh orange juice in an airless tank at temperatures below 80° F.

This same basic method is still used today. To make up for the loss of some flavor and aroma during evaporation, a small amount of fresh, unconcentrated juice is added back to the concentrate. The resulting mix is then frozen and pasteurized. Finally the processed concentrate may be shipped to a juice packager, who adds filtered water to the mix until it reaches the right brix level, a measure of soluble sugar content. For cans of frozen orange concentrate, packagers aim for a brix level of 42°, which is three times more concentrated than fresh juice. For ready-to-drink reconstituted juice, packagers aim for a brix level around 12° which is about the same as fresh juice.

Frozen orange juice concentrate was immediately popular with consumers; even in Florida, it far outsells freshly-squeezed juice. Other frozen juice concentrates followed, especially apple and grape juices, although they were not nearly as popular as orange juice. Research scientist George Speri Sperti obtained a patent for freeze-drying orange juice concentrate.