I don’t need to tell you that oven temperature is important. It’s how chemical reactions take place that transform your product. That’s why temperature needs so much attention—so many things are happening at once!
Oven Temperature has a key roll in 3 areas:
Development:
- Killing of yeast cells: 50–60°C (122–140°F)
- Maximum enzymatic activity: 60°C (140°F).
- Start of starch gelatinization: 55–65°C (130–150°F)
- Denaturation of gluten proteins at 50°C (122°F) and coagulation at 70–80°C (160–180°F).
- Start of dough-crumb transition process: 85°C (185°F)
- Inactivation of naturally-occurring and added enzymes inside the dough: 70–85°C (160–185°F).
Drying:
- Water molecules at the dough surface absorb latent heat and start to evaporate: 200–300°C (390–570°F)
Color formation:
- Maillard browning: 105°C (220°F)
- Sugars caramelize: 160°C (320°F)
That’s why you need to track and monitor how your product is changing in the oven, and adjust the temperature accordingly.
How is oven temperature controlled?
Automatically:
- A temperature sensor (thermocouple probe) senses, measures, and transmits the temperature (controlled variable) of the air inside the baking chamber.
- As the demand for hot air increases or decreases (e.g., in moments when the load of the oven increases, the temperature goes down. Then, fuel combustion must increase to return oven temperature to its set point).
- A change in oven temperature is sensed and converted to an electrical signal, amplified, and sent to a controller that evaluates the signal and sends a correction signal to an actuator.
- The actuator (gas valve) opens or closes to adjust the flow rate of the air and fuel (carbureted mixture) in the burner (manipulated variables) to keep flame intensity such that it can consistently deliver the power required. In this way, the temperature of the baking chamber is returned to its predetermined value.
Manually:
- Dough pieces are loaded into the oven, where heat from the energy sources is used to bring the products to the required temperature in order for them to cook and dry.
- A thermometer is used to measure the temperature of the product (the measured variable). The temperature is observed by an operator who adjusts the flow of air and gas in the burner (the manipulated variables) to keep the baking chamber at the constant set temperature.