Making the most of convection cooking

Sunset, May, 1994 by Linda Lau Anusasananan

Sunset's tests show the advantages of cooking with hot air

PROFESSIONAL CHEFS HAVE long favored convection ovens for baking and roasting. The main reasons: speed and even cooking and browning. Now these ovens are becoming widely available to home cooks, and they are particularly worth exploring if you cook a lot, or are looking for a more versatile oven.

TWO BASIC SYSTEMS

In a convection oven, moving air conveys the heat. A fan continuously circulates the air, maintaining a constant temperature throughout the oven; the hot air surrounds the food, quickly penetrating and cooking all surfaces evenly.

The result is consistent browning--without the need to move pans, or turn or stir the food--even during multi-rack cooking. Cooking times can be faster as well, depending upon what's being cooked.

There are two basic convection systems. One has heating elements on the top and bottom just like a conventional oven. With this design, air heats inside the oven cavity as the fan circulates it over the heating elements.

In the rear-element convection oven, often touted as the "true" convection oven, a concealed heating element surrounding the fan--outside the oven cavity--warms the air, then blows it back inside. (Some ovens have variations on this theme, such as heating elements embedded in the oven floor.)

Does one system work better than the other? We didn't find much difference when we conducted tests in seven major manufacturers' built-in convection ovens. Both systems produced good results most of the time.

Yet Michael Heintz of University Electric in Santa Clara, California, suggests that a rear-element convection system may perform better in some circumstances. With an oversize pan on the bottom rack, you'll get better air circulation. And when there's no hot element under the pan, there's less chance of burning when using the lowest rack position. Also, prolonged multilevel cooking may be more even when heat comes from the back rather than from top and bottom.

SHOPPING CONSIDERATIONS

Convection options are most often offered in top-of-the-line ranges and wall ovens. A few portable countertop ovens and small microwave-convection combinations are also available.

Prices range from $200 for counter-top models to $2,500 for some built-ins. A convection oven usually costs $200 to $300 more than a similar conventional oven. A 27-inch thermal wall oven without convection, for instance, might cost $650; with the convection feature, it could be $950.

What's the $300 advantage? Most of these ovens are two ovens in one. With a turn of a dial or push of a button, you can switch between convection and conventional heating systems.

If your kitchen has room for only one oven, this combination may be a good choice because of its versatility, convenience, and performance. You get standard bake and broil, as well as at least one convection setting. (Settings are defined differently by each manufacturer.) Additional convection cooking modes aren't essential, but they may decrease guesswork, shorten the cooking times of some foods, and improve browning over the basic convection setting.

If you're shopping for a convection oven, be sure to check an oven's inside measurements. Pans or foods with broad dimensions may not fit in some smaller European models. The capacity of many of these imports, however, is similar to wider ovens because they can cook four or five levels of food at a time--and many manufacturers provide pans with the ovens.

WHAT TESTING FOUND

For best results, manufacturers suggest following their cooking recommendations to take advantage of the design and features of their particular oven. This is good advice if you find the suggestions work fairly consistently, and if you like the results.

Sometimes, a manufacturer's literature contradicts itself, is confusing, or doesn't include what you want to cook. If results aren't to your liking, manipulate the temperature to get the results you want.

In our tests, we roasted a chicken and baked--one at a time--a pound cake, a yeast bread, and three pans of cookies.

General guidelines

Air circulation is important. Don't cover racks with foil. Allow 1 to 1 1/2 inches around pans (also above and below pans for multirack baking).

For maximum browning, use pans with low sides, and rimless cookie sheets. Many ovens come with special pans and racks that lift roasts so air flows all around. If possible, place the long sides of the pan parallel to the oven door.

Cakes, cookies, muffins, quick breads, yeast breads

A convection oven produces more even browning, slightly greater volume, and, sometimes, a lighter texture.

Reduce oven temperature 25 |degrees~ from conventional recipes. Preheat oven. Cooking time may be the same or 10 to 25 percent less than in conventional baking.

For most baked goods, temperature adjustment is critical to the texture: the moving hot air cooks the outside first and could solidify the structure before it has a chance to rise, producing a heavy, dense result.

Convection-baked cookies are superb. We baked three pans of sugar cookies at a time in preheated ovens, reducing the temperature 25 |degrees~. Unlike a standard oven, which requires switching pans midway to achieve consistent results, the circulating hot air baked all the cookies evenly without changing pan positions, and in a slightly shorter time. Some ovens accommodate four or five pans.