Performance characterization of a traditional wood-fired pizza oven

Abstract

Neapolitan pizza, a renowned Italian food recognized as one of the traditional specialties guaranteed (TSG) by European Commission Regulation no. 97/2010, should be exclusively baked in wood-fired ovens for approximately 90 s. Despite its extensive use in restaurants and rotisserie shops all around the world, such equipment has been very poorly studied thus far. The aims of this study were to characterize the operation of a pilot-scale wood-fired pizza oven from its start-up phase to its baking operation and assess its thermal efficiency. To manage brick firing, the oven was lighted at a firewood feed rate (Q_fw ) of 3 kg/h for just 1 h on the first day, 2 h on the second day, 4 h on the third day, and approximately 8 h on the fourth day. Independent of its lighting frequency, after 4-6 h, the oven vault or floor temperature approached an equilibrium value of 546 ± 53°C or 453 ± 32°C, respectively. The initial oven floor temperature gradient was linearly related to Q_fw , while the maximum floor temperature tended to an asymptotic value of 629 ± 43°C at Q_fw = 9 kg/h. The well-known water boiling test was adapted to assess the heat absorbed by a prefixed amount of water when the pizza oven was operating in pseudosteady-state conditions at Q_fw = 3 kg/h. The thermal efficiency of this oven was 13 ± 4%, and this value was further confirmed by other baking tests with four different white and tomato pizza products. PRACTICAL APPLICATION: Although wood-fired pizza ovens are largely used all over the world, little is known about their transitory and pseudosteady-state regime performance. This study shows how to perform the start-up procedure of pilot-scale equipment and, independent of the operator's ability, how to achieve pseudosteady-state conditions using different firewood feed rates. Finally, its thermal efficiency was assessed by water heating and pizza baking tests, which allowed a rough estimation of firewood consumption.

Keywords: baking test; energy consumption; thermal efficiency; transitory and pseudosteady-state regime performance; water heating test; wood-fired pizza oven.