Heat science
What heat does to food — the complete science
Heat is not a single phenomenon. At different temperatures, heat does fundamentally different things to food — denatures proteins, gelatinises starch, produces Maillard compounds, evaporates water, renders fat, and transforms aromatic molecules. Understanding which temperature does which thing is the most important practical knowledge in cooking.
Temperature Map of Indian Cooking
What happens at each temperature
- 50–60°C: yogurt bacteria die. Paneer proteins begin tightening. Enzymes in vegetables deactivate.
- 60–80°C: proteins begin denaturing (chicken becomes opaque, eggs begin setting).
- 80–90°C: starch gelatinises — dal thickens, rice grains soften, kheer develops body. Milk proteins denature for paneer making.
- 100°C: water boils. No further temperature rise in water-based cooking without pressure.
- 140°C+: Maillard reaction begins. Onion, spice surfaces produce complex aromatic compounds. This is the bhuno temperature range.
- 160–180°C: deep frying range. Rapid surface dehydration, Maillard browning, steam pressure prevents oil penetration.
- 180–200°C: tadka range. Spice aromatic compounds extract into fat within seconds.
- 200°C+: pyrolysis begins — burning produces acrid, bitter compounds instead of aromatic ones.
The Science
Why can't you make good curry on low heat?
Good curry requires the Maillard reaction, which begins at 140°C. Boiling water cannot exceed 100°C. The Maillard reaction cannot occur in water. This is why the bhuno stage is essential — it drives off water and allows the masala temperature to exceed 140°C in the remaining oil. Without bhuno, curry is cooked entirely at 100°C and can never develop Maillard complexity — it will always taste boiled rather than cooked.
30 second read
Why Pressure Cooking Changes Flavour
A pressure cooker raises water's boiling point to approximately 120°C by increasing internal pressure. This higher temperature speeds up starch gelatinisation and protein denaturation — dal softens in 20 minutes instead of 2 hours. However, 120°C is still below the Maillard threshold of 140°C, so pressure-cooked food cannot develop Maillard complexity. The correct technique: pressure cook for softness, then bhuno the masala separately for flavour.