Consider the Fork: A History of How We Cook and Eat

by Bee Wilson

Harry Brearley was a Sheffield man who invented stainless steel in 1913 as a way of improving gun barrels; inadvertently, he improved the world’s cutlery.

Before the adoption of cooking pots, around 10,000 years ago, the evidence from skeletons suggests that no one survived into adulthood having lost all their teeth. Chewing was a necessary skill. If you couldn’t chew, you would starve.

In 2003, scientists at Kyushu University in Japan fed one group of rats hard food pellets and another group softer pellets. In every other respect the pellets were identical: same nutrients, same calories. After twenty-two weeks, the rats on the soft-food diet had become obese, showing that texture is an important factor in weight gain.

When we eat chewier, less processed foods, it takes us more energy to digest them, so the number of calories our body receives is less.

Kitchen tools do not emerge in isolation, but in clusters. One implement is invented and then further implements are needed to service the first one. The birth of the microwave gives rise to microwave-proof dishes and microwavable plastic wrap. Freezers create a sudden need for ice cube trays. Nonstick frying pans necessitate nonscratch spatulas.

A patent for Nicolas Appert’s revolutionary new canning process was issued in 1812, and the first canning factory opened in Bermondsey, London, in 1813. Yet it would be a further fifty years before anyone managed to devise a can opener.

Pots enabled consumption of a far wider range of foods: many plants that had previously been toxic or at least indigestible became edible, once they could be boiled for several hours.

Hot-stone cookery transformed these plants through hydrolysis, a process liberating the digestible fructose from the carbohydrate.

With clay pots, cooks could easily boil up small grains, such as wheat, maize, and rice, the starchy staples that would soon form the mainstay of the human diet the world over. Pots thus worked in tandem with the new science of agriculture (which also emerged around 10,000 years ago) to change our diet forever.

The reason is that properly boiling water moves chaotically and transfers heat to the food several times faster than simmering water. The heat transfer also works quicker when there is more water in the pan in proportion to the food. A large pan with plenty of water and not too many vegetables in it will cook far faster than a perfectly tailored little copper pan crammed to capacity.

Copper is a wonderful conductor of heat; the only pan metal more conductive is silver. But pure copper is poisonous when it comes into contact with food, particularly acids. Copper pans were thinly lined with neutral tin, but over time the surface of the tin wore down, exposing the copper beneath.

Over time, no matter how carefully you treat it—shunning metal utensils, shielding it from searing heats—the nonstick surface of a PTFE-treated pan will simply wear away, leaving you with the metal underneath, which rather defeats the purpose.

A 1.4 mm stainless steel pan with a 0.1 mm layer of copper attached would increase its ability to even out hot spots (temperature uniformity) by 160 percent.

There’s a very easy way to check for hot spots in your own pans. Just sprinkle plain flour over the surface of a pan and put it over a medium-high heat. You will see a brown pattern start to form as the flour burns.

The earliest examples of stone cutting tools date back 2.6 million years to Ethiopia, where excavations have found both sharpened rocks and bones with cut-marks on them, indicating that raw meat was being hacked from the bone.

You get a sharp edge when two surfaces—known as bevels—come together at a thin V-shaped angle. If you could take a cross section through a sharp knife, you would see that the typical angle for a Western kitchen knife is around 20°, or one-eighteenth of a circle.

Japanese ones, which are thinner, can sharpen at around 15°. This is one of the reasons so many chefs prefer Japanese knives.

Ceramic knives cut like a dream through soft fish fillets or yielding tomatoes but are far too fragile for heavy chopping.

For a blade that is sharp, hard enough, and strong, nothing has yet supplanted steel, which can form and hold a sharp edge better than other metals.

Steel is no more than iron with a tiny proportion of added carbon: around 0.2 percent to 2 percent by weight. But that tiny bit makes all the difference. The carbon in steel is what makes it hard enough to hold a ...

But until the 1920s, and the invention of stainless steel, the taste of lemony fish was liable to be ruined by the tang of blade metal from the knife. The acid in the lemon reacted with the steel, leaving a foul metallic aftertaste that entirely overpowered the delicate flesh of the fish. This explains the production of fish knives made of silver in the nineteenth century.

Stainless steel (otherwise known as inox steel or nonrusting steel) is a metal alloy with a high chromium content. The chromium in the metal forms an invisible layer of chromium oxide when exposed to the air, which is what enables stainless steel to remain resistant to corrosion and also splendidly lustrous.

One of these long-handled instruments was the salamander, a utensil named after a mythical dragon that was supposed to be able to withstand great heat.

Each inch that you move a piece of beef nearer to the fire doesn’t just make it a bit hotter; it makes it a lot hotter. With a big roast, the “sweet spot,” or optimum position for roasting without charring, will be as much as three feet from the fire.

Experiments have shown that a cup of flour may vary in weight from 4 to 6 ounces, just by changing the degree to which the flour is sifted and airy or tamped down. This makes the difference between a cake that works and one that doesn’t; between batter that is far too thick and batter that is watery and thin.

The United States is today one of only three countries not to have officially adopted the French metric system. The other two are Liberia and Myanmar (Burma).

For one thing, thermostats only measure dry heat and take no account of humidity. We know that moisture content in the oven hugely affects the way something cooks: whether it roasts or steams or bakes, and, if so, how fast.

Now we use the word “refined” to mean rich or posh, but originally refining referred to the degree to which a food was processed. Refined food was what refined people ate.

Unlike the traditional Western procession of individual courses, Chinese dishes are set on the table to share communally, with everyone picking at the same time.

Japanese chopsticks tend to be shorter than Chinese ones (around 22 cm as against 26 cm), and they have pointed ends rather than flat ones, allowing for the most minute specks of food to be picked up.

the Indian custom is that hands should not be dipped into a basin of water, where they are recontaminated with the dirt they give off, but should be showered with a stream of fresh water for each person.

For true politeness, in most cultures where food is handheld, only the thumb, forefinger, and middle finger are used. (As with the various knife-and-fork rules, there are exceptions. Couscous, because it is so fragmented, may be eaten with all five fingers.)

Until Louis Pasteur, it wasn’t known that there is a class of microbe that can flourish without air: to kill these, the crucial factor is thorough heating.

In 1917, only 25 percent of households in the United States were on the electric grid. By 1930, that number was 80 percent. A critical mass of consumers with access to electricity was a crucial factor in the spread of the electric compressor refrigerator.

Fridges gave rise to new storage products such as plastic wrap (invented in 1953 as Saran Wrap) and Tupperware (first sold in 1946).

The potential for frozen food improved dramatically with the introduction of the “two-temperature refrigerator” in 1939—the refrigerator-freezer.

By 1925, Birdseye had developed an entirely new method for quick-freezing food, using metal plates chilled in calcium chloride solution to –45°F. Packets of food were pressed between the metal belts and froze almost instantly—far more quickly than in any previous technique.

Only in 1930 was it found that peas and other vegetables needed to be blanched in hot water before they were frozen, to inactivate the enzymes that made them spoil.

In other words, by the late 1990s, the British had just about caught up with where Americans were fridgewise in 1959.

A 2006 survey by the Institute of Food Technologists found that although 75 percent of Americans ate dinner at home, fewer than one-third were cooking their meals from scratch.

Sous-vide proteins are different: they are cooked to the same degree all the way through. And in contrast to the meat cookery of the past, you sear it after it has cooked, not before (without this final searing stage, sous-vide meat is pallid and moist).

The least desirable room to work in would have been the scullery (hence the term scullery maid), which was the place for doing all the unpleasant pedestrian jobs: peeling vegetables, gutting fish, and washing dishes, no easy job when your only tools were boiling water, grimy rags, and soap.