Food Preparation: High Altitude Cooking
What is high altitude?
Areas that are 3,500 feet above sea level are considered to be high-altitude areas.
Cooking at high altitude
All cooking processes are directly affected by atmospheric pressure.
At sea level, water boils at 212º F, but on mountaintops and other high-altitude regions, the boiling point is much lower.
For about every 500 feet of ascent, the boiling point is lowered 1ºF.
At a 7,000 foot elevation, water would boil at about 198º F. Because the water is boiling at a lower temperature, it would take longer to cook food by boiling.
Baking at high altitude
Atmospheric pressure is less at high altitudes than at sea level or more normal elevations.
This lower pressure affects the baking of cakes in several ways.
Heat rises from the bottom of an oven, but since there isn't sufficient air pressure from above to balance this upward pressure, the cake tends to expand too rapidly.
Air cells in the cake can break and escape because of this too-rapid expansion, resulting in a cake that will dip or fall.
Batter may overflow the pan due to the too-rapid expansion of the cake.
Cakes can remain underdone if temperature is not raised to adjust for the lower boiling point at high altitudes.
Due to rapid evaporation of liquids at high altitudes, cakes must be carefully timed to avoid excess dryness.
High-altitude conversion tips
To convert standard recipes into those that can be used for high-altitude baking:
- Use 5% more flour to disperse the leavening action and slow down the rapid rise of the cake.
- Use 20% more water to counterbalance the rapid evaporation of liquids at high altitudes and the extra flour added to the cake batter
- Bake about 25 degrees higher to help "set" the cake's crust
- Reduce baking time by about 20% to prevent overbaking at the higher temperature
- Fill pans 1/3 to no more than 1/2 full to avoid batter overflow caused by rapid cake expansion.
- Use cold water and large, cold eggs to give cake extra strength
- Generously grease and flour cake pans to prevent cake from sticking
- Remove top oven rack to prevent cake from sticking to it, since high-altitude cakes rise higher
- Have oven calibrated by a serviceperson periodically, since some thermostats are affected by altitude
High-altitude cookie adjustment
Only cookies with lots of chocolate, nuts, or dates need adjustment: Reduce baking powder/soda by 1/2.
At very high altitudes, a slight reduction of sugar may help.
Answers to other high-altitude questions
For other questions, consumers should contact one of the following:
- The home economics department of a local state college
- The state agricultural extension service
- The home service department of the local utility company