Pressure Cooking - Use at High Altitudes

Use At High Altitudes

A pressure cooker can be used to compensate for lower atmospheric pressure at high elevations. The boiling point of water drops by approximately 1°C per every 294 metres of altitude (1°F per every 540 feet of altitude), causing the boiling point of water to be significantly below the 100 °C (212 °F) at standard pressure. Without the use of a pressure cooker, boiled foods may be undercooked, as described in Charles Darwin's The Voyage of the Beagle (chapter XV, March 20, 1835):

Having crossed the Peuquenes, we descended into a mountainous country, intermediate between the two main ranges, and then took up our quarters for the night. We were now in the republic of Mendoza. The elevation was probably not under 11,000 feet . At the place where we slept water necessarily boiled, from the diminished pressure of the atmosphere, at a lower temperature than it does in a less lofty country; the case being the converse of that of a Papin's digester. Hence the potatoes, after remaining for some hours in the boiling water, were nearly as hard as ever. The pot was left on the fire all night, and next morning it was boiled again, but yet the potatoes were not cooked.

At higher altitudes, the boiling point of liquid in the pressure cooker will be slightly lower than it would be at sea level. When pressure cooking at high altitudes, cooking times need to be increased by approximately 5% for every 300 metres (1,000 ft) above 610 metres (2,000 ft) elevation.

Lightweight pressure cookers as small as 1.5 litres (0.40 USgal) weighing 1.28 kilograms (2.8 lb) are available for mountain climbers. Sherpas often use pressure cookers in base camp.