a low-temperature oven, the basic equipment of the baked goods sections of confectionery factories. The confectionery oven consists of a furnace, a heat transferring device, and a baking chamber.
Confectionery ovens are classified according to their heating conditions (periodic or continuous), the construction of the hearth (stationary, sliding, rotating, or conveyor), the heater system (with ducts, fire tubes, or a contact system), the heating method (solid, liquid, or gas fuel or electrical energy), and the number of baking chambers (single-level or multilevel). Continuous conveyor ovens are most frequently used for baking such flour goods as cookies and galettes. A tunnel structure and a conveyor hearth permit such a confectionery oven to be included in a mechanized production line. Depending on size (the ovens are usually between 15 and 30 m long and from 1 to 3.5 m wide), the ovens bake from 3 to 9 tons of goods in eight hours.
The ovens are made of brick or metal, with a continuous chain or belt conveyor. Whereas the chain conveyor is fitted with trays, the steel belt conveyor receives the dough products directly from the molding machine. Brick conveyor confectionery ovens, usually having a duct heating system, are heated by solid, liquid, or gas fuel burned in the external furnace. Brick confectionery ovens are very large and consist of two stories, with the furnace in the basement. Such ovens can be converted to gas by installing several flameless injection burners in the furnace.
Metal conveyor confectionery ovens with a steel frame lined with double walls of sheet steel with insulation between them are heated by gas or electricity. Gas metal ovens are equipped with small flame burners. The gas burns directly in the baking chamber or, sometimes, in the furnace, from which the combustion products are distributed along ducts around a metal muffle. The temperature in a confectionery oven is automatically maintained at 220°-280°C. Metal conveyor ovens heated by a system of electric heating units or infrared lamps have a number of advantages, including ease in regulating baking conditions, the potential for automating control over the baking process, and the use of relatively small units.
For the baking process to proceed correctly in the confectionery oven, it is necessary to regulate not only the temperature but also the relative humidity of the atmosphere.
REFERENCESMikhelev, A. A., and N. M. Itskovich. Raschet i proektirovanie pechei khlebopekarnogo i konditerskogo proizvodstva, 2nd ed. Moscow, 1968.
Spravochnik konditera, 2nd ed., part 2. Moscow, 1970.