Invention of electric oven

Electric ovens were available as early as the 1890s. However, at that time, the technology and distribution of the electricity needed to power these early electric appliances still needed improvements.

The Carpenter Electric Heating Manufacturing Company invented an electric oven in 1891. An electric stove was exhibited at the Chicago World's Fair in 1893. On June 30, 1896, William Hadaway was issued the first patent for an electric oven.

The electric oven is a heating chamber which is meant for baking foods by means of conversion of electrical energy to heat or thermal energy. Due to vast improvement in technology, the new and interesting idea of an electric baking oven was brought about by an American Engineer called Dr. Percy Spencer. By late 1946, the Ray Theon Company had filed a patent suggesting that baking ovens can be used to cook food, baked bread and pre heat food.

The first electric stoves use heating elements made of high-resistance metal to produce heat. The cooktop (range) surface had one or more circular heating elements, insulated with compressed magnesia and sheathed in a spiral metal tube. Heating elements for the oven are of similar construction but an elongated loop to distribute heat. Elements were made as plug-in consumer-replaceable parts and could also be easily removed for cleaning.
Invention of electric oven

Ohmic heating

Both irradiation and microwave heating employ radiant energies which affect foods when their energy is absorbed whereas ohmic heating raises the temperature of foods by passing an electrical current through the food.

Ohmic heating is one of the newest methods of heating foods. Ohmic heating’s major advantage is that is simultaneously heats solid pieces and liquids in a food with minimal destruction. It has been shown that Ohmic heaters can provide an interesting alternative to heat exchanger for thermal processing applications.

Georg Simon Ohm (1789-1854)

In 1827, German physicist, Georg Ohm published his treatise: Dei galvanische Kette, mathematisch bearbeite where he described what is today known as Ohm’s law.

But recognition of the thermal effects of electricity within a conductor was first elucidated by James Prescott Joule in 1840.

This resulted in a number of patents on the heating of flowable materials in the latter part of the nineteenth century. The ‘electric pasteurization’ process was used for milk treatment in six states in the United States in the 1930s.

In the 1980s, Ohmic heating was introduced by APV, who licensed the technology from the Electricity Council of Great Britain.

During this time the technology has achieved some industrial applications that include pasteurization of liquid eggs and processing of fruit products. Ohmic heating has shown good potential for blanching, evaporation, dehydration, fermentation, extraction, sterilization and pasteurization of food products.
Ohmic heating