Friday, October 24, 2014


We all must be familiar with microwave ovens now-a-days due to its advantage of fast and better cooking. In America, 90% of the homes use microwave oven for cooking. In India yet the percentage is some less but it is becoming very popular that more and more people are adapting microwave cooking.

Let’s have a picture of the story how it was invented. It is very interesting to know that microwave oven was invented accidentally in a lab. Actually there was no research going on to find better and faster way of cooking.

During a Radar related research project around 1946, Dr. Percy Spencer was working as an engineer with Raytheon Corporation. A new vacuum tube called Magnetron (a tube that produces microwaves) was being tested in the lab. Dr. Spencer discovered something unusual one day. He found that a candy bar kept in his pocket had melted.

This amazed Spencer very much. He then tried another experiments. He pointed the magnetron tube on a bag of popcorn kernels and stand at a distance away. He observed the popcorn cracked and popped all over his lab.

Next day, he tried again with an egg. What he found…the egg was exploded in few seconds. All these three experiments compelled him to come to a conclusion that in each case due to the exposure to low density microwave energy, food can be cooked faster just like candy bar, popcorn and egg.

Experimentation started with other engineers at Raytheon on Spencer’s new idea to refine it for practical use.

Spencer fed a metal box with microwave power using an opening and made arrangement that this energy was unable to escape. When food was placed in the box, temperature of food rose rapidly.

By late 1946, the Raytheon Company had filed a patent proposing that microwave energy can be used to cook food.

In 1947, Spencer demonstrated the world's first microwave oven and called it a "Radarange".

The oven that heated food using microwave energy was placed in a Boston restaurant for testing.

Commercially, ‘Radarange’ microwave ovens was marketed by Raytheon company in 1954. It was too much large, expensive and rated at 1600 watts. It was practically used in restaurants only. 

They were 5 ½ feet in length, weighed 750 pounds and cost $5000 each unit. Also Magnetron tube got heated whenever used, so it need to be water cooled. There were plumbing installations in each unit for cooling.

In 1967, Amana, a division of Raytheon, introduced its domestic ‘Radarange’ microwave oven, marking the beginning of the use of microwave ovens in home kitchens. 

In succeeding years, Litton and a number of other companies joined the countertop microwave oven market. By 1975, sales of microwave ovens would, for the first time, exceed that of gas stove ranges. America's cooking habits were being drastically changed by the time and energy-saving convenience of the microwave oven.

Although Initial sales of microwave ovens were disappointing due to so many disappointing features but further improvements and refinements with the passage of time produced a light weight, more reliable, less expensive and new air cooled magnetron which required no plumbing system.

An expanding market has produced a style of microwave oven to suit every taste; a size, shape, and colour to fit any kitchen, and a price to please almost every pocketbook.

Industries began using microwaves to dry potato chips and roast coffee beans and peanuts. Meats could be defrosted, precooked and tempered. The microwave oven had become a necessity in the commercial market and more practical uses are being added to it..the list is just endless.

No comments:

Post a Comment