Unit 1 Key terms

Find out the meaning of the following terms:

oven

an insulated box

a heat source

simple conduction

infrared heating

forced-air convection

infrared oven

conventional oven

cavity

to stack

a deck

adjust

convection oven

efficiency

Reading: cooking equipment ovens

An oven is an insulated box with a heat source that is used to cook food. There are a variety of heat sources: simple conduction of heat through the metal lining and racks of the oven, either natural convection or forced convection by a fan, infrared heating, or micro­waves. Among the various types of ovens, those that are most common in commerical foodservice are conventional, forced-air con­vection, microwave, and infrared.

Conventional Oven

The conventional oven is the most basic form of oven. A heat source is placed in the cavity of an insulated box. Heat moves through the oven using natural convection movement, reflecting the basic principle that hot air rises and cold air falls. This type of oven has been around almost as long as fire has been used for cooking.

The oven sits singularly by itself, is stacked with one or two others, or serves as the base for a range. The only controls are for temperature and, possibly, a timer. This oven is used for general-purpose baking and roasting. Heating elements are either gas, placed below the bottom deck, or electric, which can be placed on the top and the bottom. Some electric ovens have controls so that the user can adjust both the top and bottom heat to arrive at the desired outcome.

Convection Oven

For energy efficiency, the oven should not be preheated for more than 20 to 30 minutes. In loading, it is best to limit the amount of time the door is open so as to reduce heat loss, and items should be spaced as evenly as possible for even cooking.

The convection oven was originally developed by the U.S. Navy to increase the efficiency of the standard conventional oven. Because of their higher capacity and more rapid cooking, convection ovens are the main workhorses of high-volume kitchens. A convection oven is usually a stand-alone oven; heat is moved within the oven cavity by a fan. The movement of the hot air results in more rapid cooking at a lower temperature and allows more food to be cooked at one time. The cooking temperature reduction of 50°F and the 25% to 30% reduction in cooking time produced by the rapid movement of hot air also save energy (see Figure 8.8).

Mechanical Oven

Large-volume bakeshops need ovens that can cook a large volume of foods evenly. The mechanical oven was developed for that purpose. The difference between a mechanical oven and others is that in a mechanical oven the tray on which the food sits rotates inside the oven on a device similar to a Ferris wheel. While the trays rotate, the pans stay level. The cavity of the oven is heated with either gas or electricity. The rotation of the food in the oven provides for even browning, as well as easy loading and unloading because the trays are always at a convenient height.

Microwave Oven

A microwave oven cooks by using short electromagnetic waves to vibrate food molecules, which causes friction and then heat. How­ever, the cavity of this type of oven is not heated. Microwave ovens have limited application for foodservice operations. They are im­practical to use for high-production needs because cooking time increases with the amount of food placed in the oven. This type of oven produces a limited amount of microwaves; therefore, the more food in the oven, the less contact each item has with the microwaves, and the slower the cooking. The outside of the food is heated by the microwaves while the inside of the food is heated by conduction. The microwave oven's primary use in commercial foodservice is in re­heating small quantities of food.

Infrared Oven

The infrared oven is used primarily in counter operations and small table-service restaurants that need a fast, general-purpose cooking device that occupies a minimal amount of counter space. This type of oven uses radiant heat, with sources located in the top and bottom of the oven cavity. Infrared ovens are used for reheating individual portions, small pizzas and sandwiches, and items that require a short time in a very hot oven.