A question that came up from the community was how do induction cooktops work so if you are interested in finding this out, please take a quick look through this post to find out how. Human Beings have been cooking food for over a million years. We cook food because it changes its texture and it becomes easier to eat, its flavor is enhanced and the biggest advantage is that it kills all bacteria and other harmful organisms from it.
Until the invention of electricity, all food was cooked over the fire by burning wood, coal, kerosene or gas. With the advent of electricity, we have cooktops with an electrical element to generate heat and provide a clean smoke-free cooking environment. Microwave ovens provide an alternate cooking method where high-frequency microwaves directly heat the water molecules in the food items to heat them. Induction cooking is another novel way to use electricity to cook food.
What is induction?
To understand induction cooking I will first explain what is induction. Induction is a shortened form of Electromagnetic Induction. Electricity and Magnetism are interconnected to each other by the common phenomenon of electromagnetism, which means each form of energy can be converted to each other. To explain it simply, if we pass an electrical current through a coil of wire it will produce magnetism around it and conversely, if a coil is rotated inside a magnetic field it will produce electrical current. This is the same principle which makes electric motors run and dynamos generate electricity. It is due to electromagnetic induction that when a circuit with an alternating current flowing through it generates similar alternating current in a similar circuit placed near it without any physical connection.
Design of the Induction Cooktop
An induction cooktop looks quite similar to a ceramic cooktop with clear marked zones of various sizes to pots and pans for cooking. The surface is a highly scratch resistant glass-ceramic plate. Just underneath this area, there are spiral of coils normally made of copper. Once you turn on the cooker to heat, alternating current passes through these coils. This high-frequency electricity is produced by a series of electronic and electrical components of the cooker which includes a transformer, a rectifier, and an inverter. This frequency is about a 1000 times higher than your normal electricity from the wall socket.
How is the pan heated?
Now as you put your pan on the heating zone, the magnetic field produced by the coils of the cooker, induces what is called eddy currents in the base of the pan. Due to resistance to the electrical current within the metal of the pan, the electrical energy is converted to heat energy and the temperature of the pan rises. Most of the temperature rise occurs due to this resistance and rest comes from the changes in the magnetic structure of the pan and this is called magnetic hysteresis losses.
Controlling the temperature
You can control the temperature of the food being cooked by touching the high or low buttons. This in turn increases or decreases the current in the coils which in turn increases or decreases the current produced in the pan corresponding heat thereby the controlling the temperature.
It is interesting to note that the surface of cooker plate is not heated but the bottom of the pan is directly heated in the process. This results in quick heating of the food. Any heating of the cooking surface is only due to the heated bottom surface of your pan.
Testing the cookware
Since Induction Cooktops only work with iron or steel utensils an easy way to test whether your pot will work with induction cooktop or not is to test with a magnet. If the magnet sticks then your cookware is usable on the induction cooktop.
Advantages of Induction Cooktop
• This cooking method is very energy efficient as heat is not dissipated in the surroundings but the pan is heated directly at about 84% efficiency.
• Cooking is much faster as the food temperature rises quickly to your desired levels.
• The ceramic-glass top is very easy to clean.
• There is no open flame or a hot spot of the cooker surface (except which is heated by the bottom of a hot pan).
Disadvantages of Induction Cooktop
• Usually, Induction Cooktops are more expensive than ordinary gas or electric cooktops. However, the prices are falling continuously as this type of cooker get popular.
• Induction cooktops only work with pots and pans made of iron or stainless steel. Utensils made of copper, plastic, glass or ceramic will not work on these cooktops.
• Some Induction cooktops produce a little noise when operating due to their cooling fan.
• Induction cooktops are not recommended for persons who have electronic devices such as pacemakers implanted, as there is a chance of radio-frequency interference with them.
Induction Cooktops is still a niche market but their popularity is increasing as their prices are falling. Some companies have developed Induction cooktops that also work with non-ferrous pots and pans; however, they are expensive and not very popular. One of the reasons induction cooktops being not very popular is that we are used to seeing the flame or red heating coils, so some manufacturers have added simulated LED flame to make the customer comfortable with the cooker.
A selection of popular Induction Cooktops is also outlined below – feel free to view larger of compare further by clicking on any of the images provided below…
Finally, it would be greatly appreciated by the community if you can share your own thoughts on how induction cooktops work by leaving a comment in the comment box below – So that people in the community can learn also!