At high altitude, you’ll need a slow simmer. The results you get when cooking any meal are affected by temperature, humidity, and altitude. That’s why cooking is as much art as science. None of us have consistent atmospheric conditions in our kitchens so we have to use memory, senses, and perception to determine if a batter looks wet enough or the cookies should brown a minute longer in spite of what the recipe says.
Driving through the Sacramento Mountains in my slightly underpowered RV, I am acutely aware of the extent to which heat and altitude affect my ability to gain speed or maintain it as I climb. I have food with me I can microwave for dinner, but I begin to wonder how high I am and whether I’ll need to adjust my cooking times.
Altitude is stable and predictable. That means it can be adjusted for with relative consistency. If your kitchen is located from sea level to 2000 feet above, you may not have to adjust at all or so slightly that you don’t need to think twice about it. At 3000 feet and above, there is a more noticeable need for adjustment.
As you ascend above sea level, the air begins to contain less oxygen and atmospheric pressure. This is why pilots who fly unpressurized aircraft are advised to use supplemental oxygen above 10,000 ft. Less oxygen and atmospheric pressure mean water boils at a lower temperature and takes longer to boil.
Other foods also cook slower and take longer. In addition, baking requires special attention to rapid evaporation and the fact that leavening expands more at high altitude.
Turning up the temperature on the stovetop doesn’t help.
Let’s use boiling water as an example. Water cannot exceed its boiling point unless you increase pressure (like in a pressure cooker). Since water boils at a lower temperature at higher altitude, turning up the heat will only make it evaporate faster. It won’t make it hotter.
If you’re going to braise, simmer, or stir-fry meat or poultry, you’ll need to increase the cooking time and increase moisture to keep them from drying out. How much longer? At 5000 feet, it can take up to one-fourth longer for meat to cook. If you’re at 3000 feet, a shorter extension is required.
When deep frying, the lower boiling point of the water content in the foods will require lowering the temperature of the fat to prevent food from over browning on the outside while leaving the inside under-cooked. The decrease will depend on the food being fried, but roughly expect to lower the temperature of the oil about 3° F for each increase of 1,000 feet in elevation.
Be sure to have a meat thermometer on hand. In a high-altitude environment, it can be your best friend. Using a thermometer increases safety and helps prevent over and under cooking.
Eggs will need longer cooking times in high altitude as well. Again, don’t worry about turning up the heat, just increase the duration.
With slow cookers, the lower boiling point can make it difficult to get the food to reach a safe internal temperature. Use the high temperature setting for at least the first hour and increase cooking time. Be sure to keep the lid on. It takes longer than you imagine to regain the heat lost from opening the lid. It may also be helpful to put a piece of aluminum foil under the lid to keep the heat from dissipating.
To keep things confusing, oven temperatures are not affected by high altitude so baked meats can be prepared as if you are at sea level. Relying on the oven can be helpful if you’re making a transition to high altitude cooking. I won’t have that luxury in the RV. I’ll be using the microwave.
Meat and poultry will require the full recommended microwave cooking time, but I may need to reduce time for other foods that dry out quickly. Now seems to be the time to add a meat thermometer to my RV kitchen.
Winding through the mountains on a curvy two-lane highway is more interesting than weaving through trucks on the interstate. It also means my driving and my cooking rely on a long, slow simmer.