Kitchen appliances have made our lives infinitely easier than our ancestors’. It’s hard to imagine getting by without using the refrigerator, dishwasher, microwave or stove. But it wasn’t always this way; throughout their history, kitchen appliances took years of development to perfect, and improvements are being made to all of them even today.
In the Middle Ages, Europeans built fires on brick hearths and cooked in cauldrons hung above them. Sixteenth century inventors began looking for ways to make cooking safer and more efficient. The heat chamber, a rudimentary stove, enclosed fire on three sides with brick and was covered by an iron plate to set a pot on. In the early 1800s, Benjamin Thompson invented a large iron stove, which had one fire and several holes where pots could be hung. A smaller iron stove was invented in 1834. Soon, inventors improved iron stoves by adding oven compartments, and covering open holes with rings to place pots on. Early gas stoves, developed in the mid-1800s, were large, but soon the oven was integrated into the base, and the size reduced to fit into most kitchens. By the 1930s, electric stoves grew more popular than gas. Glass-ceramic cooktops emerged in the 1970s.
While researching radar in 1946, Percy Spencer discovered microwave cooking when a chocolate bar in his pocket melted while he was testing a vacuum tube called the magnetron. Spencer built a metal box into which he fed microwave power. When food was placed in the box and microwave energy fed in, the temperature of the food rose very rapidly. The first units, available in 1947, were very large and expensive, and had to be water-cooled, which necessitated plumbing installations. Soon, improvements produced a smaller microwave with an air-cooled magnetron, and sales increased. Microwaves were first used in restaurants and food-processing plants, but Tappan introduced a home model in the mid-1950s. In 1967, Amana released the first countertop microwave, which was smaller, safer and less expensive. By the mid-1970s, about 60 per cent of U.S. households owned a microwave.
In the1800s, several inventors attempted to create a dishwashing machine, but none of them worked efficiently. In the 1880s, society hostess Josephine Cochrane grew tired of finding her china chipped by the servants who washed it, so she vowed to create her own dishwashing machine. Cochrane understood that jets of water would work best to clean dishes. She made wire racks to hold dishes and arranged them in a copper boiler. A motor turned the racks around while hot soapy water was squirted up and over the dishes. Initial sales were disappointing, because the machine required huge amounts of hot water, which took hours to heat. Only hotels and restaurants bought them, but her concept led to more successful designs later. Other companies produced dishwashers powered by steam and designed for restaurants that worked by passing racks of dirty dishes on a conveyor belt under jets of hot water. The first electric dishwasher was introduced in the 1920s but it didn’t catch on with the public until the mid-1940s.
Before refrigerators, people used other preservation techniques, such as salting and canning, but they altered the taste and nutrients of food. Keeping food cold was the only way to prevent alteration, but iceboxes were inefficient and burdensome. Experiments with artificial refrigeration began in 1748, and Oliver Evans designed the first refrigeration machine in 1805. Soon, Michael Faraday discovered that liquefying ammonia causes cooling. Jacob Perkins invented the first refrigerator in 1834 using the vapour compression cycle, in which volatile liquids are evaporated to absorb heat. Early refrigerators used toxic gasses, such as ammonia, to cool, but many consumers died from inhaling the gasses. An alternative, Freon, was invented in the 1930s, but it was banned in the 1990s because of its effects on the environment. Early refrigerators were made of a wood cabinet and a water-cooled compressor. In the 1920s, steel and porcelain cabinets replaced wood. Through the 1960s, refrigerators were improved with additions like automatic defrost and ice makers.
Modern Advances in Appliances
In recent years, scientific advances have brought new technology to the appliances we use everyday. Induction stoves, which use electromagnetic induction, have caught on well. Convection ovens cook food much faster than conventional ovens. Microwaves can store cooking times for dozens of items so you can cook with the touch of a single button. Newer dishwashers feature built-in disposals, so pre-rinsing isn't even needed. New high-tech refrigerators can defrost an item when notified by e-mail, and some feature television screens mounted on the outside.