Just a bit of info regarding high altitude cooking, for those that didn't know. This is not the complete article and you are welcome to visit the website to read it in its entirety: http://www.fsis.usda.gov/factsheets/High_Altitude_Cooking_and_Food_Safety/index.asp
High Altitude Cooking and Food Safety
What is considered 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* 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.
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.
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 atmospheric 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 of pressure; at 5,000 feet with 12.3 pounds of pressure; and at 10,000 feet with only 10.2 pounds of 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 retain moisture.
Why must cooking time be increased?
As altitude increases and atmospheric pressure decreases, the boiling point of water decreases. To compensate for the lower
boiling point of water, the cooking time must be increased. Turning up the heat will not help cook food faster. No matter how high the cooking temperature, water cannot exceed its own boiling point - unless if using a pressure cooker. Even if the heat is turned up, the water will simply boil away faster and whatever you are cooking will dry out faster.
How do high altitudes affect the cooking of meat and poultry?
Meat and poultry products are composed of muscle, connective tissue, fat and bone. The muscle is approximately 75% water
(although different cuts of meat may have more or less water) and 20% protein, with the remaining 5% representing a combination
of fat, carbohydrates and minerals. The leaner the meat, the higher the water content (less fat means more protein, thus more water).
With such high water content, meat and poultry are susceptible to drying out while being cooked if special precautions are not
taken. Cooking meat and poultry at high altitudes may require adjustments in both time and moisture. This is especially true for meat cooked by simmering or braising. Depending on the density and size of the pieces, meats and poultry cooked by moist heat may take up to one-fourth more cooking time when cooked at 5,000 feet. Use the sea-level time and temperature guidelines when oven-roasting meat and poultry, as oven temperatures are not affected by altitude changes.
And I found this in a Traeger manual: