As more cooks choose convection ovens over conventional ovens for their baking needs, they discover that adjustments must be made in order for their favourite recipes to evenly cook. Not only do you have to adjust the oven temperature and consider using different baking pans in a convection oven, you also must convert the cooking times recommended in your recipes.
Cooking Time Adjustments
The heat inside a conventional oven is stagnant. Once the oven preheats to a set temperature, it periodically cycles on and off to maintain the level of heat, but the heat does not move, which creates hot and cold spots in the oven's interior. Convection ovens have fans that keep the air in the oven constantly moving around the food, which cooks foods around 25 to 30 per cent quicker than a conventional oven. To convert a conventional recipe's cooking time for a convection oven, simply reduce it by 25 per cent. Depending on the oven, you may have to increase or reduce cooking times to achieve optimum results.
In addition to adjusting cooking and baking times, you must also alter temperatures to successfully cook in a convection oven. Most conversion guides recommend reducing the suggested conventional oven temperature by around -3.89 degrees Celsius when using a convection oven. Depending on the performance of the oven, this temperature adjustment requirement may vary.
In a conventional oven, food is commonly placed as closely to the centre of the oven as possible to cook it evenly from all sides. Conventional ovens only have top and bottom heating elements, so they cook from both these angles. Convection ovens have three elements: one in the back, one on top and one on the bottom. They also have a fan in the back that distributes the hot air around the pots and pans to cook foods more evenly.
Other Cooking Tips
If the recommended cooking time in a conventional recipe is 15 minutes or less, adjust the temperature for the convection oven but not the cooking time. Always check items five to 10 minutes prior to the assumed cooking time to avoid overcooking or over baking. Some cooking professionals recommend preheating both types of ovens to 10 degrees C above the recommended baking temperature and turning the temperature down 10 degrees C after placing the food into the oven, since the interior temperature quickly decreases when the oven door is opened. Use shallow pans and baking trays for convection oven cooking to maximise the surface of the food's exposure to the heat. Covered foods and those cooked in deep pots cook better in conventional ovens.