Test Kitchen tips: Oven accuracy

Checking for accuracy:

• Most oven problems can be traced to calibration.  If this is off, your oven won't work at the right temperature; a difference of as little as 25 degrees can make or break a fragile recipe such as custard. If you think the temperature gauge is inaccurate, test it against a little oven thermometer; these handy items are available at many supermarkets and most cooking supply stores. If your oven is off, you can often fix this yourself; many ovens can easily be recalibrated but check the owner's manual to be sure. Otherwise, call a service professional.

Maintaining accuracy:

• Always be gentle when opening and closing the door.  Slamming the door will almost always throw off your oven's calibration.
• Check the gasket around the door to make sure that it's attached and properly fitted.  A loose gasket will allow heat to escape.
• Make sure any vents are unobstructed.

Making the most of your oven:

• Unless the recipe states otherwise, place your items in the center of the oven, preferably on the center rack where the heat is most consistent.
• If baking multiple racks of items, such as cookies, rotate the trays (top to bottom, front to back) for more even baking.
• Remember that various materials — glass, metal (light and dark) and ceramic — react differently to heat and will produce varying results.
• Avoid opening the oven door unless necessary. It may be tempting, but an open door allows heat to escape.