Our Methods

Salt is the first preservative and the first industrial commodity. Salt works at Poiana Slatinei in Romania date to around 6050 BC; Chinese records describe salt harvesting at Lake Yuncheng by 6000 BC. Egyptian natron preserved both fish and pharaohs, using precisely the same osmotic principle.

Salt built roads and empires. Rome's Via Salaria was the salt road, and Roman soldiers received a salarium — a salt allowance — which is where the word salary comes from. Control of salt underwrote Venice's wealth, Liverpool's, and the gabelle tax that helped bring on the French Revolution.

The chemistry was only explained in the nineteenth century: salt lowers water activity below the level at which spoilage bacteria can function, while enzymes inside the food keep working slowly. That gap between 'nothing can rot' and 'the food keeps changing' is the whole reason cured food develops flavour rather than merely surviving.

Residue analysis of pottery from Jiahu in Henan province shows a fermented rice, honey and fruit drink being made around 7000 BC. Bread, beer, wine, cheese, soy sauce, vinegar and yoghurt are all fermentation; so is the sauerkraut carried on sailing ships that ended scurvy on long voyages.

Lactic acid bacteria already live on the surface of vegetables. Submerge shredded cabbage in a 2% salt brine and you have simply tilted the odds: the salt suppresses the spoilage organisms and the lactobacilli, which tolerate it, take over and drop the pH below 4.

Pasteur identified the microbes in the 1850s, but the technique needed no theory. Every culture on earth ferments something, and almost all of them worked it out before writing.

In 1795 the French government offered 12,000 francs to anyone who could keep an army fed on the march. Nicolas Appert, a Parisian confectioner, spent fourteen years on the problem and found that food sealed in glass and then heated would keep indefinitely. He published in 1810 and collected the prize.

He had no idea why it worked — Pasteur's germ theory was fifty years away. That same year Peter Durand patented the tin canister in England, and within a generation canned food was feeding navies, expeditions and cities.

In southern Italy and Spain it stayed domestic and became ritual: the August conserva day, when a family bottles enough tomatoes to reach next August. That is the tradition our jarring room follows, not the factory one.

Direct-fire cooking is the original technique. Evidence of controlled fire use for food goes back hundreds of thousands of years, and the ember-roasting of vegetables — burying a whole pepper, onion or root in the ashes — survives in nearly every cuisine.

In Navarra it became a protected craft. Piquillo peppers are still roasted whole over vine cuttings and peeled by hand, because machine peeling requires steam or lye and both wash away the smoke that the fire has just put there.

The chemistry is Maillard browning and caramelisation happening on the skin while the flesh steams inside its own jacket — a two-stage cook from a single heat source.

Sugar cane travelled west through Persia and Egypt and reached Europe with Arab traders. For centuries fruit conserves were sold by apothecaries as medicine, not food — the word marmalade comes from marmelada, the Portuguese quince paste taken as a digestive.

By the seventeenth century the French confituriers had worked out empirically that unlined copper produced a better set than any other pan. It took another three hundred years for chemistry to explain that copper ions strengthen the pectin network.

The tradition survives in its purest form in Alsace, where small copper-pan preserves are made in batches of a few dozen jars and sold to three-star cheese trolleys.