A pressure cooker raises the boiling point of water by increasing atmospheric pressure inside the vessel — typically to 1.5 atmospheres, producing a boiling temperature of 120°C instead of 100°C. This higher temperature dramatically accelerates every water-based cooking reaction: collagen conversion occurs in 30–45 minutes instead of 3–4 hours; starch gelatinisation is complete in minutes; Maillard reactions can occur in water (impossible at atmospheric pressure) within the pressurised vessel. Modernist Cuisine makes the case that pressure cooking produces fundamentally better stock than conventional methods — higher temperatures produce more gelatin extraction and more flavour compound development in a fraction of the time.
- Conventional stock at 100°C: collagen conversion complete in 4–8 hours; minimal Maillard products in the liquid - Pressure cooker stock at 120°C: collagen conversion complete in 45–90 minutes; Maillard products form in the liquid itself (producing a deeper, more complex flavour than conventional stock) - Bone marrow: melts completely at 120°C, distributing into the stock - [VERIFY] Modernist Cuisine's specific pressure cooking stock parameters. **Applications:** - Beef stock: 45 minutes at full pressure produces a stock comparable to 4-hour conventional stock - Chicken stock: 30–45 minutes at full pressure - Bean cooking: soaked beans in 15–20 minutes; unsoaked in 30–40 minutes - Caramelised onion: 5–7 minutes at full pressure produces 45-minute stovetop results
Modernist Cuisine Vol. 2