You might notice that Council’s pound cake recipe doesn’t contain any chemical leaveners (neither baking soda nor baking powder). That's relatively common among pound cakes, but here it serves an added purpose: Cakes and cookies rise faster at higher altitudes, sometimes reaching their peak before they’re fully baked, which then causes them to collapse. So as you ascend, you might want to decrease the leavener in whatever cake or cookie recipe you’re carrying with you. From 3,000 to about 6,000 feet, Hampton suggests you “decrease the leavener by 25%–at 7,000 to 8,000 feet you might decrease by 30%. Higher than that, you might have to make some more drastic changes.”
Nuts and other mix-ins have a tendency to sink into cakes, quick breads, and other baked goods, too. Council’s best trick for making any recipe with a streusel or crumb coating, such as coffee cake? Hold onto the topping until halfway through the cooking time, and then quickly sprinkle over the half-baked batter before finishing.
About that cooking time: In general, Council says “most things will bake more quickly at altitude than they will at sea level.” The main exception here is fruit pies. Because the boiling point of water is lower at high elevation, the liquid doesn’t get as hot. Said another way, at sea level, water boils at 212°F. At 8,000 feet, water boils at 197°F. That means, as long as there is moisture in your mountain-made pie, the interior temperature will never go higher than 197°F. Therefore, the fruit inside the pie cooks more slowly. (Need to speed things up? Council says metal pie pans are the way to go as opposed to ceramic or glass.)
Hampton points out that bread recipes can also be finicky wherever you’re baking. At elevation, it’s especially important to pay attention to the rising time of your loaves. Lower air pressure means that yeast doughs and sourdoughs both have a tendency to rise more quickly at high elevations than at sea level. If you’re in a hurry, that’s great news, but if you are trying to develop more flavor in your breads, you may want to let your dough do all its rising in the fridge.
No matter what you’re baking, both writers agree that high elevation bakers should use visual cues, not a recipe’s suggested baking time, as their primary guide. Try not to mess with the suggested temperature, though. “When you start adjusting temperature,” says Hampton, “it changes the recipe and brings in other complications: you’ll see too much browning too quickly, for example.”
For more on the science of individual baked goods, we return again to Purdy. She wrote these tips for Epicurious a few years back, but they still apply today.
Why does changing elevation affect baking?
Wherever you cook or bake, results depend on many factors, including food chemistry, atmospheric pressure, climate, and elevation. The higher you climb, the thinner the air and therefore, the lower the atmospheric pressure. Beginning 2,500 feet above sea level, altitude starts to affect all cooking, but especially baking, in three significant ways:
1. The higher the elevation, the lower the boiling point of water (212°F at sea level, 206.7°F at 3,000 feet, 203.2°F at 5,000 feet, 199°F at 7,000 feet, 194.7°F at 10,000 feet). When water boils at lower temperatures, it takes longer for foods to cook in or over water.
