Grilling and Broiling

Grilling and broiling are the most intense dry-heat methods — both use infrared radiation to deliver energy directly to the food surface at very high temperatures (400–500°F+ at the grate or element). The difference is directional: grilling heats from below, broiling from above. Both produce rapid surface dehydration, intense Maillard browning, and characteristic flavor development from fat drippings combusting on hot coals or elements.

Heat transfer mechanism

The primary mechanism is infrared radiation — electromagnetic energy emitted by hot coals, heated metal, or gas/electric elements. Radiation travels through air without heating it, delivering energy directly to the food surface. Grilling adds a secondary mechanism: conduction from the hot grill grate, which creates the characteristic seared grill marks.

Heat Transfer in Cooking

All cooking is heat transfer — getting thermal energy from a source into food. Three physical mechanisms do this work, and every cooking method is a particular combination of them. Understanding the three forms explains why different methods produce different results, why pan material matters, and why heating times vary with food size and shape.

Conduction: direct contact

Thermal energy passes from one particle to a nearby one through collision. The mechanism differs dramatically by material:

Microwave Cooking

Microwave ovens heat food through a mechanism fundamentally different from every other cooking method: electromagnetic radiation at a specific frequency directly excites polar molecules — primarily water — causing them to rotate. Molecular friction from this rapid rotation generates heat from within the food, bypassing the surface-in heating that defines conventional cooking. The result is extraordinary speed but an inability to brown, crisp, or develop the complex flavors that come from high-temperature surface chemistry.

Roasting and Baking

Roasting and baking surround food with hot air in an enclosed oven, combining convection (air circulation) with radiation (from oven walls and elements). The result is the most even dry-heat method — heat reaches all surfaces simultaneously rather than from one direction as in grilling. Typical oven temperatures (300–500°F) dehydrate food surfaces, enabling Maillard browning and caramelization while the interior cooks through by conduction.

Heat transfer mechanism

Hot air rises from the heating element, cooler air sinks, creating convection currents that circulate heat throughout the oven cavity. Oven walls and elements also emit infrared radiation that heats food surfaces directly. The pan itself conducts heat to the food’s bottom surface. Forced convection (fan-assisted) ovens accelerate air movement, producing more uniform temperatures and faster cooking.