Serendipitous Invention – Microwave Ovens

Serendipitous Invention - Microwave OvensIntroduction: The Three Princes of Serendip, where Serendip is the Classical Persian name for Sri Lanka, is a fairy tale in which the protagonists ‘were always making discoveries, by accidents and sagacity, of things they were not in quest of.’ Based on this, Horace Walpole coined the word serendipity in 1754 to mean inventions or discoveries made by accident. Science and technology offer many anecdotes of serendipitous discoveries and inventions. Here is the first such story in a series about serendipitous, patented inventions.


In 1945, Percy Spencer, an engineer working for the Raytheon Corporation, was carrying out some experiments with radar. One day, as he worked, he noticed that a chocolate bar (apparently a bar of Mr. GoodbarTM) in his pocket had begun to melt. He was perplexed and went on to investigate it further.

Percy was using a magnetron in his experiments. A magnetron is a vacuum tube used to generate microwaves within the radio frequency in the range of 0.3 to 300 GHz. He placed some corn kernels near a magnetron in operation and they began to pop. He realised the potential applications of this discovery and went to develop what would eventually become the microwave oven. Raytheon obtained a patent for this invention.

In 1947, Raytheon introduced the first microwave oven to the market. Its commercial name was “Radarange”. This innovative appliance used microwave radiation to heat food, and thereby cooking it quickly and efficiently. This revolutionised the way people cooked. For a long time, after our ancestors started using fire for cooking, all cooking had used fire. Later, with the advent of electricity, electric stoves and ovens came into use. These too heated the food by supplying heat from the outside, as fire had done.

Fire or a heating coil heats the food directly as in a barbecue or heats the utensil which heats the food by thermal conduction. Alternatively, fire or electricity heats air which, in turn, transfers the heat to the food as in convection ovens. Microwaves, on the other hand, supply electromagnetic energy to the water molecules in the food without heating the utensil or the air around it. The water molecules in the food absorb microwave energy and jiggle rapidly, in other words, they heat up. Therefore, we can say that microwaves heat the food from inside and hence this was a revolutionary way of cooking.

Initially, microwave ovens were large and expensive. They were used mainly in commercial establishments such as restaurants and cafeterias. Soon, as technological advances and improved manufacturing processes made microwave ovens more compact and less expensive, it became more accessible to the average consumer. By the 1970s, it had become common in households across many parts of the globe. It offered unprecedented convenience in the kitchen. Words such as microwaving and microwaved soon entered the dictionary.

The widespread adoption of microwave ovens transformed cooking practices and food consumption habits. With the ability to heat, defrost, and cook a wide variety of foods in a fraction of the time required by conventional methods, microwave ovens democratized cooking and food preparation, making cooking easier for busy individuals and families.

Moreover, microwave ovens paved the way for the development of convenient packaged foods specifically designed for microwave cooking, further streamlining the cooking process. From microwaveable popcorn to frozen dinners, these innovations catered to the growing demand for quick and easy meals in a fast-paced world.

Beyond its impact on home cooking, the microwave oven has also influenced various industries, including food manufacturing and packaging. Manufacturers began designing packaging materials and containers that were microwave-safe, enabling consumers to heat and serve meals directly from the packaging – a testament to the profound influence of this humble kitchen appliance. For the calorie-conscious, microwave ovens offer an alternative to deep frying and roasting over fire of certain food items.

Microwave ovens have also given rise to microwave safe plastics. It has also helped spread the use of glass and ceramic utensils even in cultures where metal and earthenware utensils were the only prevalent options.

It is ironic that, even after six decades in use and numerous studies having found no connection between the use of microwave ovens and any adverse health effects, fears about it persist. There are frequent claims on social media that some Japanese company or the other has stopped manufacturing microwave ovens because it is dangerous to human health. As Mark Twain famously said, about his own obituary, the reports about the demise of the microwave oven are “exaggerated.”

Worldwide, microwave oven is a staple not only in domestic kitchens but also in offices and restaurants. The microwave oven is continuing to evolve with advancements in technology and culinary preferences. While its invention may have been serendipitous, the lasting impact of the microwave oven is clear to see. It has fundamentally changed the way we cook, eat, and live, leaving an indelible mark on the culinary landscape.

Author: J L Anil Kumar

First Published by: Lexology Here