High-altitude cooking

Last updated

High-altitude cooking is cooking done at altitudes that are considerably higher than sea level. At elevated altitudes, any cooking that involves boiling or steaming generally requires compensation for lower temperatures because the boiling point of water is lower at higher altitudes due to the decreased atmospheric pressure. The effect starts to become relevant at altitudes above approximately 2,000 feet (610 m). Means of compensation include extending cooking times or using a pressure cooker to provide higher pressure inside the cooking vessel and hence higher temperatures.

Contents

Boiling

At sea level, water boils at 100 °C (212 °F). For every 152.4-metre (500 ft) increase in elevation, water's boiling point is lowered by approximately 1°F. At 2,438.4 metres (8,000 ft) in elevation, water boils at just 92 °C (198 °F). Boiling as a cooking method must be adjusted or alternatives applied. Food will take longer to cook, or could not be prepared at all depending on temperatures required.

Methods used at high altitudes

A pressure cooker is often used to compensate for the low atmospheric pressure at very high elevations. Under these circumstances, water boils at temperatures significantly below 100 °C and, without the use of a pressure cooker, may leave boiled foods undercooked. Charles Darwin commented on this phenomenon in The Voyage of the Beagle : [1]

"Having crossed the Peuquenes (Piuquenes), 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."

Boiling point of pure water at elevated altitudes

Based on standard sea-level atmospheric pressure (courtesy, NOAA):

Altitude, ft (m)Boiling point of water, °F (°C)
0 (0 m)212°F (100°C)
500 (150 m)211.1°F (99.5°C)
1,000 (305 m)210.2°F (99°C)
2,000 (610 m)208.4°F (98°C)
5,000 (1,524 m)203°F (95°C)
6,000 (1,829 m)201.1°F (94°C)
8,000 (2,438 m)197.4°F (91.9°C)
10,000 (3,048 m)193.6°F (89.8°C)
12,000 (3,658 m)189.8°F (87.6°C)
14,000 (4,267 m)185.9°F (85.5°C)
15,000 (4,572 m)184.1°F (84.5°C)

Source: NASA. [2]

Related Research Articles

<span class="mw-page-title-main">Boiling point</span> Temperature at which a substance changes from liquid into vapor

The boiling point of a substance is the temperature at which the vapor pressure of a liquid equals the pressure surrounding the liquid and the liquid changes into a vapor.

<span class="mw-page-title-main">Troposphere</span> Lowest layer of Earths atmosphere

The troposphere is the lowest layer of the atmosphere of Earth. It contains 80% of the total mass of the planetary atmosphere and 99% of the total mass of water vapor and aerosols, and is where most weather phenomena occur. From the planetary surface of the Earth, the average height of the troposphere is 18 km in the tropics; 17 km in the middle latitudes; and 6 km in the high latitudes of the polar regions in winter; thus the average height of the troposphere is 13 km.

Atmospheric pressure, also known as air pressure or barometric pressure, is the pressure within the atmosphere of Earth. The standard atmosphere is a unit of pressure defined as 101,325 Pa (1,013.25 hPa), which is equivalent to 1,013.25 millibars, 760 mm Hg, 29.9212 inches Hg, or 14.696 psi. The atm unit is roughly equivalent to the mean sea-level atmospheric pressure on Earth; that is, the Earth's atmospheric pressure at sea level is approximately 1 atm.

<span class="mw-page-title-main">Barometer</span> Scientific instrument used to measure atmospheric pressure

A barometer is a scientific instrument that is used to measure air pressure in a certain environment. Pressure tendency can forecast short term changes in the weather. Many measurements of air pressure are used within surface weather analysis to help find surface troughs, pressure systems and frontal boundaries.

<span class="mw-page-title-main">Boiling</span> Rapid phase transition from liquid to gas or vapour

Boiling or ebullition is the rapid phase transition from liquid to gas or vapour; the reverse of boiling is condensation. Boiling occurs when a liquid is heated to its boiling point, so that the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere. Boiling and evaporation are the two main forms of liquid vapourization.

<span class="mw-page-title-main">Humidity</span> Concentration of water vapour in the air

Humidity is the concentration of water vapor present in the air. Water vapor, the gaseous state of water, is generally invisible to the human eye. Humidity indicates the likelihood for precipitation, dew, or fog to be present.

<span class="mw-page-title-main">Pressure cooker</span> Device for preparing food

A pressure cooker is a sealed vessel for cooking food with the use of high pressure steam and water or a water-based liquid, a process called pressure cooking. The high pressure limits boiling and creates higher temperatures not possible at lower pressures, allowing food to be cooked faster than at normal pressure.

<span class="mw-page-title-main">Altitude</span> Height in relation to a specified reference point

Altitude is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context. Although the term altitude is commonly used to mean the height above sea level of a location, in geography the term elevation is often preferred for this usage.

<span class="mw-page-title-main">Simmering</span> Cooking technique

Simmering is a food preparation technique by which foods are cooked in hot liquids kept just below the boiling point of water and above poaching temperature. To create a steady simmer, a liquid is brought to a boil, then its heat source is reduced to a lower, constant intensity.

<span class="mw-page-title-main">Atmosphere of Earth</span>

The atmosphere of Earth is composed of a layer of gas mixture that surrounds the Earth's planetary surface, known collectively as air, with variable quantities of suspended aerosols and particulates, all retained by Earth's gravity. The atmosphere serves as a protective buffer between the Earth's surface and outer space, shields the surface from most meteoroids and ultraviolet solar radiation, keeps it warm and reduces diurnal temperature variation through heat retention, redistributes heat and moisture among different regions via air currents, and provides the chemical and climate conditions allowing life to exist and evolve on Earth.

<span class="mw-page-title-main">Slow cooker</span> Countertop electrical cooking appliance used to simmer food

A slow cooker, also known as a crock-pot, is a countertop electrical cooking appliance used to simmer at a lower temperature than other cooking methods, such as baking, boiling, and frying. This facilitates unattended cooking for many hours of dishes that would otherwise be boiled: pot roast, soups, stews and other dishes.

<span class="mw-page-title-main">Solar cooker</span> Device for cooking with the heat of sunlight

A solar cooker is a device which uses the energy of direct sunlight to heat, cook or pasteurize drink and other food materials. Many solar cookers currently in use are relatively inexpensive, low-tech devices, although some are as powerful or as expensive as traditional stoves, and advanced, large scale solar cookers can cook for hundreds of people. Because they use no fuel and cost nothing to operate, many nonprofit organizations are promoting their use worldwide in order to help reduce fuel costs and air pollution, and to help slow down deforestation and desertification.

<span class="mw-page-title-main">Sous vide</span> Cooking method using prolonged low temperatures

Sous vide, also known as low-temperature, long-time (LTLT) cooking, is a method of cooking invented by the French chef Georges Pralus in 1974, in which food is placed in a plastic pouch or a glass jar and cooked in a water bath for longer than usual cooking times at a precisely regulated temperature.

<span class="mw-page-title-main">Armstrong limit</span> Altitude where water boils at body temperature

The Armstrong limit or Armstrong's line is a measure of altitude above which atmospheric pressure is sufficiently low that water boils at the normal temperature of the human body. Exposure to pressure below this limit results in a rapid loss of consciousness, followed by a series of changes to cardiovascular and neurological functions, and eventually death, unless pressure is restored within 60–90 seconds. On Earth, the limit is around 18–19 km above sea level, above which atmospheric air pressure drops below 0.0618 atm. The U.S. Standard Atmospheric model sets the Armstrong limit at an altitude of 63,000 feet (19,202 m).

The vapor pressure of water is the pressure exerted by molecules of water vapor in gaseous form. The saturation vapor pressure is the pressure at which water vapor is in thermodynamic equilibrium with its condensed state. At pressures higher than saturation vapor pressure, water will condense, while at lower pressures it will evaporate or sublimate. The saturation vapor pressure of water increases with increasing temperature and can be determined with the Clausius–Clapeyron relation. The boiling point of water is the temperature at which the saturated vapor pressure equals the ambient pressure. Water supercooled below its normal freezing point has a higher vapor pressure than that of ice at the same temperature and is, thus, unstable.

<span class="mw-page-title-main">Effects of high altitude on humans</span> Environmental effects on physiology and mental health

The effects of high altitude on humans are mostly the consequences of reduced partial pressure of oxygen in the atmosphere. The medical problems that are direct consequence of high altitude are caused by the low inspired partial pressure of oxygen, which is caused by the reduced atmospheric pressure, and the constant gas fraction of oxygen in atmospheric air over the range in which humans can survive. The other major effect of altitude is due to lower ambient temperature.

<span class="mw-page-title-main">Cooker</span> Index of articles associated with the same name

Cooker may refer to several types of cooking appliances and devices used for cooking foods.

<span class="mw-page-title-main">Thermal cooking</span>

A thermal cooker, or a vacuum flask cooker, is a cooking device that uses thermal insulation to retain heat and cook food without the continuous use of fuel or other heat source. It is a modern implementation of a haybox, which uses hay or straw to insulate a cooking pot.

<span class="mw-page-title-main">Multicooker</span> Automated cooking appliance

A multicooker is an electric kitchen appliance for automated cooking using a timer. A typical multicooker is able to boil, simmer, bake, fry, deep fry, grill roast, stew, steam and brown food.

References

  1. Journal and remarks, Chapter XV, March 21, 1835 by Charles Darwin.
  2. Parsons, C. L.; Norcross, G. A.; Brooks, R. L. (1984). "Radiosonde Pressure Sensor Performance: Evaluation Using Tracking Radars". Journal of Atmospheric and Oceanic Technology. 1 (4): 321–327. Bibcode:1984JAtOT...1..321P. doi: 10.1175/1520-0426(1984)001<0321:RPSPEU>2.0.CO;2 . ISSN   1520-0426.