Convection ovens can deliver faster cooking times than conventional ovens because they use fans to force heated air around the cooking chamber. This feature helps break up the “cold halo” that surrounds food as it cooks. It also distributes heat more evenly, so there are fewer cold spots throughout the baking chamber, providing more consistent results and doing away with the need for rotating food during cooking.
Pan Size and Capacity
Pan capacity will likely be one of the most significant numbers for you to consider, as it will determine how much you can bake in your oven at one time. Get an idea of how many pans worth of products you'd like to bake in one batch and make that a key factor to consider while you shop. The max pan size that your oven accepts is also something to consider. These ovens will often accept half-size pans and smaller, while there is a selection that can accept full-size pans. The smallest ones can only accept quarter-size pans and smaller.
BTU and Watt Rating
BTU, which stands for British Thermal Unit, is a way to measure the amount of heat produced by gas-powered equipment. The higher the BTU rating of a given oven, the more powerful it will be, but the more gas it will burn. Wattage is a similar measurement for electric equipment. Higher-powered equipment can cook foods faster and will have shorter recovery times, meaning that they will come back up to the set baking temperature sooner after you add cold product. High-powered equipment is preferred if you'll be cooking a lot of chilled and frozen food. For finishing and reheating, a lower-powered option will probably work just fine.
Digital controls provide more customization for setting baking temperature and time. Most ovens with digital controls are also programmable, with the ability to store cooking times and temperatures for common items which can be recalled with the push of a button. This feature reduces the chance for operator error and can prevent having to throw away products because they've been baked at the wrong settings. Still, many operators prefer the simplicity and familiarity of manual controls, which are also available on these ovens.
The location of controls is important, too. Excessive heat from surrounding equipment can damage the electrical equipment. Indeed, one of the most common causes for repair calls is heat damage to the control components, so it pays to plan in advance so you can keep the controls of your oven away from the heat from other equipment like ranges, charbroilers, and griddles. You will find ovens with controls on the left side, right side, or near the bottom of the unit.
While it is common for manufacturers to build the interiors of their countertop convection oven with steel or aluminum, some coat theirs in porcelain. Porcelain reflects heat from the burners or elements, spreading it out across the baking chamber and providing a more even bake to everything in the oven. Also, because porcelain is smoother than bare metal, it is easier to clean than steel or aluminum and should last longer, since there is no potential for corrosion as long as the enamel stays on.
Most of these units have only one door, but the ones with two will have either dependent or independent ones. Dependent doors both open when only one handle is pulled. On an oven with independent doors, each door opens separately. Dependent doors can make it easier to get pans in and out, but independent ones can conserve energy if only one is opened at a time.