The Three Oldest Tools
Drying, salting and smoking are among humanity’s oldest answers to spoilage, and they often work together. All three reduce the water available to microbes, since bacteria and molds need moisture to grow. Salt and smoke add further barriers. Their origins are lost in prehistory, but archaeological and written evidence from places such as ancient Egypt and Mesopotamia shows dried and salted fish and meat in regular use.
Drying
Drying is the simplest method: sun, wind and warmth remove moisture from fruit, grain, pulses, herbs, fish and thin strips of meat. In hot, dry regions this can be done outdoors on racks or roofs. Where weather is damper, drying happens near a fire, in a kiln, or in a ventilated loft or shed.
Examples are found worldwide: stockfish, unsalted cod dried on wooden racks in cold northern air, produced in Scandinavia for centuries; biltong and jerky strips of meat; raisins, dried apricots and figs; and sun-dried tomatoes. Pemmican, a mix of dried meat and fat made by Indigenous peoples of North America, was later adopted by fur traders and explorers as a durable travel food.
Dried foods are light and compact, and later could be reconstituted with water. The main risks are rewetting, which can allow mold to grow, and insects.
Salting
Salt draws water out of food by osmosis, and most spoilage microbes cannot thrive in a high-salt environment. Dry salting packs meat or fish in salt, while brining immerses it in salty water. Salt cod, herring and anchovies, and salted pork and beef, became staple foods for populations far from the sea and for sailors on long voyages.
Salt itself was valuable. It was obtained by evaporating seawater in shallow pans, boiling brine from springs, or mining rock salt, and in many societies it was taxed or traded over long routes. Cities and regions with access to salt gained economic power, a pattern that helped shape the fishing trade of medieval northern Europe.
Salt curing of meat also introduced another ingredient in many traditions: nitrate, often found as impurities in salt or added as saltpeter. Cured meats such as ham and bacon keep a pink color and distinctive flavor because of chemicals formed from nitrates and nitrites, a link that cooks noticed long before chemists explained it. The safety of these compounds in the modern diet is debated, and regulation applies to them in many countries.
Smoking
Smoking exposes food to the smoke of burning wood, usually in a smokehouse or over a slow, smoldering fire. It dries the surface, deposits compounds with antimicrobial effects, and gives a recognizable flavor. Cold smoking, at low temperatures, is usually paired with salting and drying; hot smoking partly cooks the food.
Smoked fish, bacon, sausages, ham and cheese all come from this tradition. Different woods give different flavors, and local habits created regional products such as smoked salmon, kippered herring and various smoked sausages.
At Sea and on the Road
Preserved food made long journeys possible. Ships on the Atlantic carried salt beef, salt pork, hard biscuit and dried peas, a diet that worked as a store of calories but was monotonous and lacking in fresh vitamins. Fishing fleets salted their catch on shore or at sea, and salt cod fed trade across the Atlantic. Explorers on the sailing ships of the age of discovery, including the caravel ship, depended on such provisions, as did armies on the march.
The weakness of these foods is that they were often extremely salty, tough and unvaried. Cooks soaked salt meats and fish before use, which is a habit still seen in recipes today.
Why They Survived
When canning and refrigeration spread, the old methods did not vanish. Bacon, pastrami, salt cod, kippers and cured hams remain popular because people like how they taste. Household refrigerators ended the need for salting as a safeguard in most homes. Meanwhile, understanding of microscopic life has helped producers manage safety better, by controlling salt levels, temperature and humidity.
Home curing today follows detailed guidance from food safety authorities, since mistakes can cause serious illness. This article describes history only and does not offer instructions.