From caveman times, humanity's never-ending struggle to put food on the table (or table-shaped rock, as the case may be) always been twofold. First, our ancestors had to hunt, gather or; later, grow and harvest their food. Then they had to find some way to preserve whatever couldn't be eaten immediately. But scavengers and even insects that might horn in on ancient leftovers were the least of their worries, as our forebears soon learned the hard way: Bacteria too small to see — much less to understand, until Louis Pasteur came along in 1861 and disproved that microorganisms generate spontaneously — could swiftly make food inedible best, and deadly at worst.

For millennia, our ancestors preserved their food by drying, smoking, salting or sugaring it. These processes all had the side effect of altering the flavor and/or texture of the food being preserved. This was a good thing (think of bacon … mmm), but not always.