Canning

Canning emerged from Napoleon's army, which needed food that would not spoil during long campaigns. The French government offered a prize of 12,000 francs for a practical food preservation method, and a Parisian confectioner named Nicolas Appert spent 15 years experimenting until he found it: seal food in airtight containers, then heat them. He had no idea why it worked—germ theory was 50 years away—but the empirical result was undeniable.

Appert's method built on centuries of food preservation knowledge: salting, smoking, pickling, and drying. But these methods changed food's taste and texture. Appert discovered that heating food in sealed glass jars preserved both nutrients and flavor for months or years. He published his findings in 1810 in 'L'Art de conserver les substances animales et végétales' (The Art of Preserving Animal and Vegetable Substances).

The timing was no accident. Napoleon's Continental System had cut France off from British colonial trade, making food security a strategic priority. The government's prize incentivized systematic experimentation that peacetime commerce might never have funded. War shaped the adjacent possible.

Appert used glass jars and champagne bottles, sealed with cork and wire. Almost immediately, Peter Durand in Britain patented a tin-plated iron container—the tin can—which was more durable than glass and cheaper to produce. Bryan Donkin established the first commercial canning factory in 1813, supplying the Royal Navy.

For decades, canning remained an empirical art. Canners knew that heating prevented spoilage but not why. Some batches spoiled anyway, sometimes fatally. Only after Louis Pasteur demonstrated germ theory in the 1860s did the science catch up with the practice. Pasteurization—heating to specific temperatures for specific times—emerged from understanding what Appert had discovered by trial and error.

Canning enabled the global food trade, Arctic exploration, and modern military logistics. It separated food production from consumption in both space and time, transforming diet and commerce. A confectioner's experiments, driven by military necessity, created the foundation for industrial food preservation.