Although the concept of induction cooking was first developed back in the early 1900’s, induction cooking equipment has just recently started to catch the attention of the foodservice industry. With the refinement of the technology came lower prices and greater ease of use, and as such this effective and energy-efficient method of cooking is being integrated with increasing regularity into both commercial and residential cooking equipment. Induction cooktops feature a unique suite of benefits that are universally enjoyed by those who invest in the technology, but the cooking mechanism is rather different from most conventional methods, and knowing how it works can help you get the most out of your induction cooker.
What is Induction?
To understand exactly how food is cooked through induction, it is important to first understand the concept of induction itself. To define it in technical terms, induction is the generation of an electrical potential difference (a.k.a. voltage) in a material that has been placed within a magnetic field. In other words, induction is a method of creating electrical energy within an object without requiring direct physical contact with the source of the electricity. Materials with the “right” magnetic properties react electrically to the presence of a magnetic field, a fact which is exploited in many modern day technologies. The phenomenon of induction is one of the fundamental concepts in modern electronics, and is a critical factor in the existence of countless technologies such as wireless energy transfer, electrical power conversion, electronic motors, and—of course—cooking. In fact, induction cooktops are an elegant illustration of the concept, and are a conveniently relevant method for demonstrating how induction works.
Unlike other electric cooktops, induction cooking surfaces do not contain standard heating elements. Instead, induction ranges feature a large coil of conductive metal (usually copper) under each “eye.” When the stove is turned on, an electric current is sent through the coil, producing a local magnetic field above the eye. When an induction-ready pot or pan is placed near the coil, an electrical current is induced within the material by the magnetic field. However, every material (even conductive metals) will have a certain magnitude of natural resistance to the current being produced by the magnetic field, meaning that not all of the electrical current will pass freely through the pan. This resistance causes some of the energy from the electrical current to be converted into thermal energy, which causes the material of the pan to heat up, thereby cooking the contents inside.
In essence, induction cooktops completely skip a step by using your cookware directly as the heating element, rather than transferring heat into the pan from an external heat source. Because the induction cooking mechanism relies on the cookware to complete the heating device, induction “burners” themselves do not actually produce heat. The stovetop itself stays cool to the touch, even after removing hot pans from the surface, virtually eliminating the danger of burning oneself on a hot eye. This simplifies cleanup, as well, as spilled sauces and food particles will not burn onto the cooking surface.
Benefits of Induction Cooking
While it may seem like a complicated idea, induction cooking surfaces are very simple to use, and they offer several benefits that are unique to the induction technology. First and foremost, induction cookers are extremely energy efficient. Conventional electric cooktops utilize heated metal elements to gradually transfer heat into the cookware on top of the stove. Although effective, this method loses a significant amount of heat to the surrounding air. Because induction heats the pot directly, almost no heat is lost, and the stove therefore requires much less energy to maintain a consistent temperature.
Temperature adjustments are also very quick with induction stoves. Much like a gas stove, the energy input in an induction stove is adjusted almost immediately when you turn the knob. Changing the temperature on an induction cooktop instantaneously adjusts the intensity of the current running through the coil (thereby adjusting the power of the magnetic field and ultimately changing the temperature in the pot). Rather than having to wait for a hot burner element to adjust to the new temperature, the only variable controlling the speed at which your cookware changes temperature is the previous temperature of the pot itself. Changing the temperature from low to high will still naturally require some time to adjust, but induction cooktops will catch up to the new temperature much faster than conventional stoves.
The energy efficiency, rapid temperature adjustment, and inherent safety of a stovetop that does not actually heat up may be enough to sway your next kitchen upgrade toward including an induction cooktop, but there are, as with all things, a few drawbacks that are worth mentioning.
Drawbacks
The most important thing to note when talking about induction stovetops is that, unlike other kinds of equipment, they will not function with all types of cookware. Because of the nature of the induction process, only ferromagnetic materials will heat properly when placed on the stove. Ferromagnetism is a fairly complex topic—one that we could easily talk about for quite a few posts in a row—but the basic explanation is sufficient when discussing induction cooking. For our purposes, a ferromagnetic material is simply a metallic compound that exhibits strong magnetic properties. Iron and its common alloy, steel, are both inherently ferromagnetic cookware materials, while materials such as aluminum, copper, and ceramic are not. Many modern pots and pans will carry a symbol or notification on the packaging if they are induction-ready, but most solid stainless steel or iron pans will work. If a magnet will stick strongly to the bottom of the pan, chances are it will work with an induction stove
While buying new pots and pans is an easy solution to the previous problem, the other primary drawback—the cooking surface itself—is not quite as avoidable. Induction cooktops almost always feature glass-ceramic cooking surfaces to prevent heat transfer between the pot and the cooktop. While this reduces burn and injury potential, it also makes the cooking surface more fragile, and not particularly well-equipped for faster, more kinetic cooking techniques like sautéing. Pots and pans must be handled with care to avoid scratching, cracking, or chipping the cooking surface.
Aside from the more delicate cooking surface and limited cookware, there are few other significant drawbacks that are unique to induction cooktops. The safe, responsive, and highly consistent nature of induction stoves make them appealing to both professional and residential chefs alike, and the unique technology offers an easy to use and energy efficient alternative to standard electric cooktops. But be warned: once you have experienced the high-tech accuracy of the induction cooker, you may not be likely to turn back.
