Oven Baking Parameters
What are Oven Baking Parameters?
Oven temperature, air velocity, heat flux, and humidity are the four key parameters that can be measured and controlled, and that determine the quality of final baked products and oven energy input.
Why are the four baking parameters important?
Temperature: Temperature in each oven zone is the dominating factor in baking mechanisms including gelatinization, enzymatic reaction, and browning reaction, and therefore final bread quality.2 It is the one parameter that is the most understood and the easiest to control.
Air Velocity: Oven air velocity is the measurement of airflow in the oven. In a convection oven, the air velocity directly controls the amount of energy delivered to the product. Air velocity influences the baking time, firmness, weight loss, and color of baked products.
Heat Flux: Heat flux is the amount of energy transferred per unit area per unit time from or to a surface. It has three components: radiation, convection and conduction. Both the total amount of heat flux and the different ratios of the three components influence the baked product’s quality.
Humidity: Oven humidity influences the two important dynamic processes during baking: the energy (in the form of heat) transferring into the food, which causes starch gelatinization, enzyme reaction, etc.; and the moisture migrating from product interior to the surface and evaporating. Both processes influence baked product quality.1
How are the four parameters related?
The four oven baking parameters are interrelated. They work together to control the final product quality. Air velocity influences convective heat flux. In one study, when oven air velocity changed from 0 to 1 m/s in an experimental electric oven kept at 300 oC (572 oF), the convective heat flux increased about 4.5 times, from 3.2 to 14.5 kW/m2.3 Humidity can be controlled by air velocity and temperature. As the temperature increases, the capacity of the air to hold moisture increases.
- Xue, J., and C.E. Walker. “Humidity Change and Its Effects on Baking in an Electrically Heated Air Jet Impingement Oven.” Food Research International, vol. 36, no. 6, 2003, pp. 561–569.
- Nantawan, T., et al. “Optimisation of the Temperature Profile in Bread Baking.” Journal of Food Engineering, vol. 55, no. 1, 2002, pp. 41–48.
- Baik, O.D., et al. “Cake Baking in Tunnel Type Multi-Zone Industrial Ovens Part I. Characterization of Baking Conditions.” Food Research International, vol. 33, 2000, pp. 587–598.