Water boils at 100'C at sea level. High up in the mountains, water boils at a lower temperature. Why does it take longer to cook potatoes high up in the muontains than it does to cook potatoes at sea level?
I'm not sure, because isn't it colder in the mountains?
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Safe Food Handling
High Altitude Cooking and Food Safety
* What Is Considered a High Altitude?
* How Is the Air Different at High Altitudes?
* How Do High Altitudes Affect Cooking?
* Why Must Cooking Time Be Increased?
* How Do High Altitudes Affect the Cooking of Meat and Poultry?
* Why Is a Food Thermometer Helpful?
* Where to Place the Food Thermometer
* Recommended Internal Temperatures
* Is Egg Cookery Affected at High Altitudes?
* Is Cooking Affected When Using Microwaves at High Altitudes?
* Is Cooking Affected When Using Small Electrical Appliances at High Altitudes?
* How Do High Altitudes Affect Cooking with a Slow Cooker?
* Is Cooking Affected When Using a Pressure Cooker at High Altitudes?
* How Should Home Canning Processes Be Altered?
* Keep Hot Food Hot
* Keep Cold Food Cold
* Where to Get More Information about Cooking at High Altitudes
Fully one-third of the population of the United States lives at high altitudes. Cooking at a high altitude requires some special considerations. The thin air — less oxygen and atmospheric pressure — affects both the time and the temperature of most everything that's cooked. Where the altitude is above 3,000 feet, special cooking methods are needed for meat and poultry.
What Is Considered a High Altitude?
Most cookbooks consider 3,000 feet above sea level to be high altitude, although at 2,000 feet above sea level, the boiling temperature of water is 208 °F instead of 212 °F. Most of the western United States (Alaska, Arizona, California, Colorado, Idaho, Montana, Nebraska, New Mexico, Nevada, Oregon, South Dakota, Texas, Utah, Washington, and Wyoming) are wholly or partly at high altitude, however many other states contain mountainous areas that are also well above sea level.
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How Is the Air Different at High Altitudes?
Above 2,500 feet, the atmosphere becomes much drier. The air has less oxygen and atmospheric pressure, so cooking takes longer. Moisture quickly evaporates from everything. For this reason uncovered food will dry out quickly while cooking.
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How Do High Altitudes Affect Cooking?
At altitudes above 3,000 feet, preparation of food may require changes in time, temperature or recipe. The reason is the lower atmosphere pressure due to a thinner blanket of air above. At sea level, the air presses on a square inch of surface with 14.7 pounds pressure; at 5,000 feet with 12.3 pounds pressure; and at 10,000 feet with only 10.2 pounds pressure — a decrease of about 1/2 pound per 1,000 feet. This decreased pressure affects food preparation in two ways:
1. Water and other liquids evaporate faster and boil at lower temperatures.
2. Leavening gases in breads and cakes expand more.
As atmospheric pressure decreases, water boils at lower temperatures. At sea level, water boils at 212 °F. With each 500-feet increase in elevation, the boiling point of water is lowered by just under 1 °F. At 7,500 feet, for example, water boils at about 198 °F. Because water boils at a lower temperature at higher elevations, foods that are prepared by boiling or simmering will cook at a lower temperature, and it will take longer to cook.
High altitude areas are also prone to low humidity, which can cause the moisture in foods to evaporate more quickly during cooking. Covering foods during cooking will help hold in moisture.
Sra
SraJMcGin, your answer didn't show up..
If the temp is lower in the mountains, it takes longer to give the potatoes the same energy at a lower temperature.
Heat conducted by conduction is proportional to the product of Tempoutside*time.
Actually, the temperature in the mountains can be colder, but that's not the main reason why it takes longer to cook potatoes at high altitudes. The primary factor at play here is the lower atmospheric pressure at higher elevations.
At sea level, the atmospheric pressure is higher, which causes water to boil at 100°C (212°F). However, as you go higher up in the mountains, the air becomes thinner, and consequently, the atmospheric pressure decreases. This decreased pressure directly affects the boiling point of water.
The boiling point of water is closely tied to the pressure exerted on it. As the atmospheric pressure decreases with increasing altitude, the boiling point of water also decreases. In fact, for every 150 meters (492 feet) increase in elevation, the boiling point of water decreases by approximately 0.5°C (0.9°F).
So, when you cook potatoes at a higher altitude, the lower boiling point means that the temperature of the water is lower compared to cooking at sea level. Since the water is cooler, it takes longer to transfer heat to the potatoes and cook them thoroughly. Consequently, the cooking time for potatoes (and other food) is extended at higher altitudes.
To sum up, the longer cooking time for potatoes at high altitudes is due to the lower boiling point of water caused by decreased atmospheric pressure, rather than the colder temperature in the mountains.