The history of many kitchen appliances involves unexpected discoveries and applications, including wartime radar turned hamster defroster and replacing an 'ice king' with heat-stealing boxes.

Fascinating evolution of the oven

From ancient wood-fired ovens in Rome and Egypt to modern microwaves, the oven’s evolution has shaped how we cook. Early ovens focused on heat retention, but breakthroughs like the gas stove in 1834, and the electric stove in 1892, brought precision. Then, in 1967, the microwave redefined convenience.

Tracing the history of refrigeration

Refrigeration has become critical to most of our lives. But not long ago, it wasn't available. How did we become so dependent on our fridges and freezers? This fun, informative podcast traces the history of keeping it cool with ice and...

The food processing techniques developed for World War II, later repurposed for consumers

Research projects funded or sponsored by the military led to the development of active dry yeast to make bread easier to bake and an improved version of dehydrated cheese, which would be used in powdered cheese snacks. Freeze-drying, which had been used to ease the transport of blood plasma to battlefields, where it would be reconstituted with water, was later used on fruit for cereals.

Learn the history of food science breakthroughs from the 20th century

Long after humans developed the means to produce sufficient food to feed civilizations, scientific research focused on a wide variety of objectives, such as developing methods to preserve food quality (accomplished via frozen food), speeding up cooking (leading to the microwave), and lowering the cost of sweetening food, which high fructose corn syrup provides.

Microwave ovens heat food by agitating certain molecules with non-ionizing light

Molecules with resonant frequencies within the microwave range vibrate, producing heat between adjacent matter, just as hands warm when rubbed together. The mesh in front of an oven's door confines the microwaves to the container, while the rotating plate allows different parts of food to travel through regions of maximum vibration.

Watch a timeline of the history of electricity, from observations of static electricity in antiquity to the War of the Currents—a rivalry to establish the ideal system for electric grids.

Under certain conditions, very hot liquids can freeze more quickly than cooler ones—a phenomenon called the Mbemba effect, after the Tanzanian high school student who accidentally observed it.

In 1880, Jacques and Pierre Curie discovered that electricity could be produced by striking certain materials—the piezoelectric effect—a phenomenon that is seen in barbecue lighters.

Before transistors, which regulate the flow of electricity, vacuum tubes—glass tubes containing no gas that resemble light bulbs—served as the electronic switches in computers.

Before the invention of transistors, vacuum tubes made radio possible

Discovered by Thomas Edison, vacuum tubes allow electrical currents to travel through empty space. Later modified into a diode—keeping current flowing in only one direction—vacuum tubes allowed electronics to turn alternating current into direct current.

Agnes Marshall invented 'ices,' the Victorian equivalent of ice cream, and improved the period's hygienic practices for consuming the dessert.

Temperatures colder than Pluto can allow electricity to flow resistance-free

Since its discovery in 1911, applications of superconductivity have made MRI machines and maglev trains possible due to quantum effects at extreme temperatures. These effects are modeled as electrons cooperating in pairs and flowing more efficiently.

The frozen pizza was invented in 1950

In 1950, some pizzerias were premaking pies, allowing customers to take them home and cook them at their convenience. That same year, Philadelphia's Joseph Bucci filed a patent for a "Method of Making Frozen Pizza." Soon, frozen pizzas were appearing in grocery store aisles.

Dragon seismometers, Baghdad batteries, and more ancient artifacts

The ancients were behind us in many ways, but some inventions from the time have not been surpassed in the modern era in effectiveness, beauty, or cleverness. This quick list of bizarre ancient inventions includes a battery from Baghdad, a Molotov cocktail-like explosive in Greece, and more.

The unexpected origin story of the snow globe

In 1900, a Vienna tradesman named Erwin Perzy I was attempting to invent an inexpensive way to improve light amplification in hospital operating rooms. After experimenting with a glass globe filled with water, the idea for the snow globe struck. Industrious as well as inventive, Perzy eventually turned his idea into a successful business. Read the full article to learn how the invention grew to become recognized globally.

Washing dishware before putting it in a dishwasher may reduce the appliance's effectiveness because it dynamically adjusts wash time and temperature based on a sensor that detects dirtiness.

The history of molecular gastronomy, from thickening yolks with alcohol to making art with food

Before understanding why they worked, humans used scientific principles, including designing solutions and analyzing outcomes, to develop preservation methods like curing meat and fermenting vegetables. By the 20th century, the application of industrialized food preparation to smaller kitchens set the stage for the subdiscipline of food science.

Before 1932, when particle accelerators were first used for nuclear research, scientists relied on naturally radioactive substances to advance their understanding of the atomic nucleus.

Dilution fridges create the colder-than-space environments needed for quantum computers by successively lowering temperatures across layers plated with gold, which reduces heat transfer via radiation and gives them a chandelier-like appearance.

How to cook food with lasers

Creative Machines Lab at Columbia Engineering have developed a system of software-controlled lasers to cook food with precision, retain moisture with the final-cooked product, brown food within its original packaging, and create an entirely new meal creation process for a consumer. Watch this three-minute video to see for yourself.

Cookies were originally used as low-stakes ways to test the temperature of an oven

In 7th century Persia, bakers used small mounds of dough to test the heat in ovens before baking larger cakes. Afterward, they'd add honey, nuts, and other items to the small mounds, creating early cookies.

Heat pumps use an easily boilable chemical to regulate temperature

In air conditioners, warm air is pulled from a home to turn a refrigerant into a gas, which is then compressed, raising its temperature. The gas naturally releases this energy to the comparatively cooler environment when exposed, then expands and is reused in the system. Heaters run in reverse, with the refrigerant picking up energy from the comparatively warmer environment.

Electromagnetic induction creates electricity from a changing magnetic field

The phenomenon was discovered in 1831 by Michael Faraday when an electric current was induced in a wire wrapped around an iron ring after a second wrapped wire not connected to the first was connected or disconnected from a battery.

World War II helped convince food companies to produce more processed foods

Processed foods had existed since the 19th century, but they began infiltrating the mainstream during World War II, with foods designed to last on the battlefield for days. After the war, food companies saw great potential in the relatively cheap foods aimed at busy households. (Some readers may experience a paywall.)

If two strands of conducting materials are connected at two junctions, electricity can be generated if one junction is heated while the other is cooled—a phenomenon known as the Seebeck effect.

A dispute about the origin of twitching frog legs led to the invention of the first battery

Experiments by Luigi Galvani on exposed frog leg nerves showed activity when they were hung from iron railings and brass hooks, suggesting the existence of "animal electricity" that discharged when connected to metals. Alessandro Volta's voltaic pile, which stacked metals with an inorganic electrolyte, showed that electricity originates from chemical reactions.

30 everyday inventions originally created for space

In their pioneering work to develop the technologies necessary for humans to inhabit space, NASA and its counterpart agencies around the world have produced dozens of products millions of people use everyday. Some of these are obvious, like water filtration systems and wireless headsets, while many are surprising, like artificial limbs and insulin pumps. Dive into the list here.

Infrared light is most often associated with thermal radiation and cooking food

Although extensively used in remote controls for electronics, where LED lights send signals wirelessly, infrared cameras allow for night vision and thermography—imaging of heat patterns in the body to non-invasively reveal blood flow for supplementary diagnostics. Infrared radiation also provides heat in toasters, saunas, and other technologies.

Watch someone follow an early American recipe using 19th-century technology

Following an old cookbook, one woman makes meatballs, pastries, potatoes, and spinach over her fireplace. The springtime dinner is taken from a 1778 book titled The Art of Cookery, which remained a bestseller throughout the 1820s.

Radio waves are used in broadcasting, weather radar, telecommunications, and GPS

Its ability to bend around obstacles and reflect off the ionosphere—an electrified layer of Earth's upper atmosphere—allows this type of light to travel long distances without damaging living things due to its low energy. MRI scanners, WiFi, and Bluetooth technologies are also applications of this form of light.

In the 19th century, ice-cream-related illnesses were somewhat regular in America thanks to vendors' poor hygienic practices.

Tesla's first successful AC prototype used a metal shoe polish tin for a rotor

After leaving his position working with Thomas Edison, Tesla partnered with George Westinghouse to promote alternating current systems as a more viable, scalable solution to electricity transmission.

Iceberg lettuce was the salad staple people ate for most of the 20th century, popular due to its durability, long shelf life, and mild flavor.

Many of Wright's buildings used radiant heating

Frank Lloyd Wright’s buildings weren’t just radical because of how they looked, but many of them also incorporated stunning technological innovations. Radiant heating is one of Wright’s most popular heating systems, offering the comfort of walking on warm floors on a cold day.

Why pickles became a thing

Pickles began in Mesopotamia around 2400 BCE as a way to preserve vegetables amid heat (and spoilage). They spread through Egypt, Greece, and Rome, where Julius Caesar reportedly fed pickles to his soldiers, and brining was treated as a culinary art. The technique is broadly useful, as salt and water can extend the shelf life and deepen flavor for almost anything.

During World War II, fighter plane turbulence was used to make ice cream.

In the early 20th century, 'baby cages' were popular among parents who believed that putting their children in the cold would build their immunity to minor illnesses.

In 1898, Nikola Tesla wowed a crowd by controlling a boat with no visible connection

Some onlookers thought it was a trick, such a a monkey being inside the boat, rather than mind control or some other metaphysical phenomenon. In reality, Tesla was pioneering radio waves, proving wireless control was possible.

Despite promoting alternative current, Nikola Tesla did not invent it

The technology was developed by Hippolyte Pixii in 1832, almost 25 years before Tesla was born. Other myths about Tesla include that he invented the transformer, radio, and the induction coil, which was invented by Nicholas Callan in 1836.

Medieval European winters were colder than ours, but peasants stayed warm

Medieval winters were colder than ours today while the continent was mired in the so-called Little Ice Age. Without modern technologies, peasants survived with simple, sometimes genius, solutions, including central, chimney-less fireplaces (vented by small, draftless vents) and decorative handwarmers.

CES debuted in 1967 amid a wave of miniaturization in at-home electronics

The rapid development of integrated circuits—the basis of computing power—in the 1960s catalyzed an industrial shift toward miniature devices, including pocket transistor radios, smaller TVs, and more. This first consumer electronics trade show (with a slate of 117 exhibitors and 17,000 attendees) sought to make everyday electronics accessible and portable. See a timeline of early consumer tech with photos.

Cathode-ray tube televisions are examples of electron accelerators

CRT TVs work by converting electricity into heat, which causes electrons to be emitted from the rear of the device in three beams responsible for the colors red, green, and blue. Electromagnets direct electrons to phosphor molecules on the screen, which emit light and illuminate the pixels.

13 unconventional ways to stay cool during heat waves

While air conditioning is the default solution for many in a heat wave, it can get expensive while requiring the consumption of fossil fuel energy. So, how else can you stay cool during a heat wave? This list compiles some practical, at times quirky, suggestions, including an ice-pack-filled aubergine hat.

Validation of the greenhouse effect may have been misattributed

Although Irish physicist John Tyndall showed in 1859 that water vapor and carbon dioxide could absorb and radiate infrared radiation, experiments by American scientist Eunice Foote three years earlier identified the same phenomenon for light in general. Historically overshadowed, her work was rediscovered by female historians over a century later.

How freeze-drying leaves food with less than 4% of its original water content

In specialized equipment, foods are brought down to temperatures below freezing before a vacuum pump removes the air from the container, lowering the pressure around the food and the boiling temperature of water. Heaters beneath the food slowly raise its temperature above the now-reduced boiling point, causing the water to go from a frozen to a gaseous state.

Ice cream can be traced back to a frozen milk dish from the 7th century.

Space travel sparked inventions we now use every day

Technologies developed for space exploration produced lasting spinoff innovations—from camera phones to memory foam—displaying how the space race reshaped everyday life here on Earth

Freezer burn is the result of moisture leaving ice cream, something that's easily avoidable.

Learn about the applications of radioactivity in medical, academic, and industrial settings

Besides their use for radiometric dating by archaeologists and researchers at museums and universities, radioactive materials are used in sensors that help track ocean currents and analyze pollution, soil, and petroleum products. Radioisotope-based sensors also help measure air in ice cream and prevent spillovers when soda bottles are filled in factories.

Until late 2024, the company that makes McDonald's ice cream machines held an elusive repair monopoly on them, the culprit behind the frequent outages that fueled widespread social media discourse.