To cook in water at 150 degrees Celsius using a pressure cooker, a specific pressure must be maintained. The boiling point of water increases with the rise in pressure, which is a fundamental principle of cooking under pressure.
The boiling point of water at standard atmospheric pressure (1 atm) is 100 degrees Celsius. To achieve a boiling point of 150 degrees Celsius, a pressure of approximately 4.0 atm is required. This means that the pressure inside the cooker must be significantly higher than normal atmospheric pressure.
For practical purposes, this translates to needing to operate your pressure cooker at about 3 atmospheres above atmospheric pressure, or around 30 psi (pounds per square inch). This high pressure allows the water to reach higher temperatures than it normally would, which is essential for certain cooking methods like pressure cooking.
In conclusion, to reach a boiling point of 150 degrees Celsius, a pressure cooker must maintain a pressure of roughly 4.0 atm (or about 30 psi) to achieve those elevated cooking temperatures safely.