Gas, Electric, Induction, Convection - What Does It All Mean?

Gas has certainly been the more popular fuel choice for many years when it comes to cooktops and ranges because of its ability to heat quickly and to be controlled more precisely than electric. However, with newer technologies, and the growing popularity of induction heat, electric now has many of the same benefits that gas offers.

Gas ovens, on the other hand, are not as popular as electric ovens as their temperatures tend to fluctuate resulting in uneven cooking, but they do provide a moist heat, which can be advantageous depending on what you're cooking. Electric ovens cook more evenly and are thus the more popular oven.

Now, with advent of dual-fuel ranges, which have gas burners and an electric oven, you can have the best of both worlds in one appliance!

Gas
The heat output of gas is measured in Btus ( British thermal units per hour). Standard gas burners can generate 8,000 to 10,000 Btus, while more heavy-duty burners, as seen on professional ranges, can generate up to 18,000 Btus - the higher the Btu, the more heat exerted, the quicker your water boils and steaks sear. Many gas ranges and cooktops offer different configurations of burners with different Btu outputs allowing you to simmer on one burner and sear on another. Not only do gas burners heat quickly, they retain little heat when turned off, so cooking stops almost immediately.

Most gas cooktops and ranges today have an electronic ignition system instead of a pilot light, which means you'll need 120-volt outlet where you're placing your appliance in addition to the gas hookup.

Electric
Electric heat is measured in Watts. Standard electric burners generate about 1,200 Watts, while higher-heat burners generate 2,000 Watts or more. As with gas ranges and cooktops, electric options offer different configurations of burners with different Wattage outputs allowing you more cooking flexibility. They do provide a constant and even heat, however they heat up and cool down more slowly than gas making them more difficult to precisely control. Electric ovens produce a more constant heat than gas ovens, ultimately cooking more evenly, which is excellent for baking - the heat produced, however, is a dryer heat.

Electric cooktops and ranges have several different types of burners/elements:

• Coil Heating Element: Most of us are familiar with this type of burner, the heating coil sits above the surface of the cooktop. It's the most economical and least stylish, but provides quick and steady cooking heat, and the elevated elements allow for a variety of cookware styles and widths. Although, the heating element is exposed and vulnerable to spills and cooking mishaps, cleanup is simple as the drip pans are easy to access via removable coils, in most cases.
• Radiant Heating Element: Ceramic glass electric cooktops are one of the more popular cooktop styles available today. The smooth surface looks stylish and sleek and is easy to clean, and the radiant elements heat up and cool down quickly. Smoothtop models place the heating elements beneath a sheet of ceramic glass; they have unique conduction properties allowing them to heat quickly to cook evenly. Radiant heating element cooktops are more expensive than conventional coil-burner cooktops.
• Halogen Heating Element: Like radiant cooktops, halogen cooktops have a smooth, glass-ceramic surface with the heating elements concealed under it. They use tungsten-halogen lamps and specially-developed reflectors to direct heat upward through the glass surface, which is made of a material known as vitro-ceramic or Ceran, producing an almost instantaneous heat.

  When turned on, the halogen lamps glow red immediately and emit an instantaneous heat. When turned off, they cool down quickly. The control, speed, and responsiveness of a halogen unit makes it similar to cooking with gas. Halogen cooktops are about as expensive as induction cooktops and as efficient as radiant cooktops.

• Solid-Disk Heating Element: Solid-disk element cooktops are less common and more expensive, but gaining in popularity. They feature heating elements embedded in a cast-iron burner for consistent heating and easy cleanup. Electric resistance wires are embedded in insulation beneath the solid cast-iron disk allowing heat to spread evenly through the disk to the cookware. The cast iron surface has a burned-in, noncorrosive coating and is raised above the cooktop surface allowing spills to flow away from the hot elements.

  Some solid-disk models are thermostatically controlled denoted by a silver disk in the center of the element. Others have thermal limiters identified by a red dot in the center of the element. Because the solid disk is constructed of cast iron, the cooking surface retains its heat once turned off allowing cooking to continue with the power off. Energy is saved by taking advantage of that retained heat while you're cooking. Solid-disk cooktops, however, use more energy than the conventional coil system and, as previously mentioned, are more expensive.

Dual-Fuel
One new and increasingly popular option is the combination of gas and electric in one range, referred to as a dual-fuel range (dual-fuel is a term associated with ranges not cooktops). They're configured to offer burners powered by gas and an oven powered by electricity. Dual-fuel ranges are more expensive, so consider your style of cooking when deciding if dual-fuel is right for you.

Keep in mind that most dual-fuel ranges require a 240-volt outlet (however, you can find a few that are 120-volt). If you decided to purchase one that requires a 240-volt outlet and you don't already have one in your kitchen, you'll have to have one installed, which can add considerable cost.

Induction
Induction cooktops are more commonly found in commercial kitchens as they are expensive and usually require a large up-front investment. However, they are appearing more and more in residential kitchens, quickly gaining in popularity due to their high energy efficiency and safety (the cooktop surface never gets hot). Induction cooktops use electromagnetic energy to heat the cookware leaving the smooth cooktop surface cool to the touch and easy to clean.

Electric-powered induction coils beneath a smooth glass surface generate a magnetic field when iron or steel cookware comes into contact with the surface. Instead of heating the surface of the cooktop, the cookware itself is heated. Induction cooktops offer rapid heating and cooling, precise temperature control and thermal efficiency. The only real drawback, aside from price, is it requires magnetic cookware (iron or steel) for it to work. Don't know if you have magnetic cookware? Place a magnet (any magnet will do) on the bottom of your cookware - if it sticks, you have magnetic cookware that will work on an induction cooktop.

Convection
Convection ovens utilize a fan in the rear of the oven cavity that circulates hot air over, under, and around food. Because it circulates hot air, convection ovens cook more rapidly (30% faster than conventional ovens) and at a lower temperature, helping to retain flavor and moisture in foods. The circulating air also helps to eliminate hot spots, allowing food to cook more evenly, and speeds up the browning of roasted meats and poultry.

Convection ovens tend have a smaller internal capacity than standard ovens due to the fan, but they can cook several dishes of food at one time. In fact, the oven can be filled from top to bottom as long as there is at least an inch of space between items for the air to circulate. (In a conventional oven, items should be placed in the center of the oven to cook thoroughly.)

There are two types of convection ovens: ovens with the heating elements at the bottom of the oven; and "true" convection ovens with the heating elements at the rear of the oven, which are the preferred type as the heating elements are closer to the fan creating a more even heat. In addition, some convection systems are combined with microwave energy to offer increased speed on top of the benefits of convection. Ovens with convection and microwave energy can be expected to cut cooking times by up to 50%.

Steam
When you think about cooking with steam, you typically assume you're going to be cooking on the cooktop, however newer advancements now allow you to cook with steam in the oven too.

Steam cooking as been found to retain more vitamins than other cooking methods and is therefore touted as a healthier way of preparing foods. Dry heat cooking relies on added fat to keep meats from drying out, but with steam, the meat doesn't need any additional fat to stay moist. Temperatures of steam ovens vary - 200 degrees F to more than 500 degrees F - and cooking times are generally cut by more than half.

Steam ovens work by filling a reservoir with water to begin the baking process - installed ovens don't need to be hooked up to a water supply as the reservoir is detachable and easily accessible. A major drawback of steam ovens is it's inability to brown foods. Pre-browning meats before cooking in the oven results in more time in the kitchen, but is an option. Similarly, baked items such as breads and pies will not come out as crispy or they'll appear pale, so browning in a convention oven will be necessary.

Speed-Cooking
One of the newest and most expensive technologies for all ovens is Speed-Cooking. Speed-cooking combines heat, convection, microwave energy and a halogen-quartz light all in one oven. These functions can be used separately or together for the fastest of fast meal preparation. With speed-cooking, baking and roasting can be reduced as much as 25% of the conventional preparation time. Manufacturers often have their trademarks for this type of technology: look for trademarks such as Tri-Vection, Ultima and SpeedCook.