The World of Food: The Microwave

By Julia Maish |

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This week, we celebrate a life-changing American invention that is an integral part of kitchens all over the world, a mainstay for busy parents, college students, restaurants and convenience stores, non-cooks, and single people everywhere. Yes – December 6 is Microwave Oven Day. Who invented it? Where and when? And how did it become so ubiquitous in our lives?

As with so many other groundbreaking innovations, the microwave oven came about by accident, when its unwitting inventor, Percy LeBaron Spencer, a 51-year-old self-taught engineer who never graduated from high school, was researching something else. One day in 1945, as an employee of Raytheon Corporation of Waltham, Massachusetts, Spencer was performing tests on a magnetron – a new sort of vacuum tube – when he made an odd discovery: the candy bar in his pocket had melted. Wondering if close proximity to the tube would have the same effect on other foods, he positioned some popcorn kernels nearby, and voila! Popped popcorn everywhere. The next day, as an interested colleague watched, Spencer tried the same technique on an egg, and the colleague learned a valuable lesson: don’t stand too close. With the resulting mess and greater efficacy in mind, Spencer created a metal box into which he fed the power from the magnetron and discovered that without any avenue for the electromagnetic energy to escape, foods heated up very quickly and – presumably – safely. With that, the microwave oven was born, and by 1947, the first primitive models were hitting the commercial market.

Early incarnations of the microwave were impractical; as with the VCR, which came later, they were enormous (almost 6 feet tall, bigger than your average refrigerator at the time); heavy (upwards of 700 pounds); and expensive (they cost approximately $5,000, about $56,000 in today’s money). Also, these first microwaves required running water to cool their magnetron tubes, so separate plumbing was a necessity. Naturally, with all of these caveats, the microwave wasn’t an immediate hit. That all changed once lighter, smaller, more reliable, and less expensive models that were air-cooled became available, but they were still mostly confined to industrial use.

Then along came the Radarange, which acquired its catchy name in a Raytheon employee contest. Still large, still heavy, but more affordable. Once Raytheon acquired Amana Refrigeration in the mid-1960s and developed the first countertop microwave oven in 1967 (cost: less than $500 or $3,600 today), domestic microwave sales took off, despite false but pervasive rumors that they caused cancer, blindness, and/or impotence. Less than a decade later, more microwave ovens were sold each year than gas ranges, and they were used more frequently than dishwashers. One important result: since anyone including children can safely use a microwave, women were liberated from endless hours of slaving over a hot stove (and presumably could spend the time the microwave saved them on other pursuits), as their family members could easily cook for themselves.


TV dinner

For restaurants and vending machine companies, the microwave oven was a lifesaver: food could be kept fresh for much longer and microwaved to order, with far less waste. And microwaves made some culinary applications such as defrosting and precooking much quicker and easier. Eventually, microwaves began to be used for drying non-food items such as ceramics, leather, pencils, and tobacco.

Today’s microwaves offer more features than ever before. Some even have a convection oven built in, if you want crisping and browning functions in addition to heating. If you take a walk through any grocery store’s frozen foods section, there is seemingly no limit to the side dishes, desserts, and complete meals – family or individual size (including the ever-popular TV dinner, once aluminum trays became a thing of the past) – that you can prepare at the touch of a button, and without heating up a conventional oven or turning on the stove. And there are plenty of options in the produce section as well, as vegetables can be steamed with no fats or oils added. (And yes… as Spencer and his poor egg-drenched colleague discovered, it’s a great way to cook them, too.)

Percy LeBaron Spencer remained with the Raytheon Company until his death at age 76, and in 1999, he was posthumously inducted into the National Inventors Hall of Fame. And rightly so, as it’s difficult to imagine our daily lives without his “accidental” invention. So on Microwave Oven Day next Wednesday, be sure to heat up a frozen meal in his honor – dinner in six minutes or less!