Toast has heat conduction, convection and heat radiation. Put the bread in the baking tray and the baking tray in the oven. First of all, there is absolute heat conduction. Then, close the oven door, the air between the bread and the row of baking tubes above the oven is doing thermal convection to maintain the temperature balance during baking, and the moisture in the bread is also doing slow thermal convection. The infrared ray (thermal radiation) emitted by the baking tube installed on the stove plays a decisive role in the coloring of the bread surface.

Steamed steamed bread: heat conduction and convection, first of all, convection, through the action of hot steam, make each steamer do thermal convection movement, and then conduction, convection and conduction exist in steamed bread, so that heat can be transferred smoothly in steamed bread.

Take pancakes as an example, that is, heat conduction and convection, with heat conduction as the main factor and convection as the supplement. The thermal radiation is scattered to other places, and the amount acting on the product is almost zero.