Two preservation experiments from the Civil War: condensed milk and essence of coffee. Condensed milk was milk that had been dried out into a liquid paste. One could add water to it and reconstitute it, then add it to coffee. Since the milk was pasteurized in the thickening process, this worked out rather well. Then, there was essence of coffee… they tried to do the same thing, by drying out huge vats of coffee into a thick brown sludge for canning. This was not quite as successful. In theory, one would take a bit of the essence-goo, mix it with water, and have instant coffee. In practice, the “essence” was so foul that most soldiers refused to drink it.
Information from The Mariners’ Museum Civil War Collections
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