Yep! I'm back in Mexico, I was only in the UK for Christmas.
The altitude is a nightmare here, changes everything!
Ohhhh the high-altitude explains so much! But much to your credit you keep tackling your baking projects over and over again until you make it work. Kudos!
Almost all recipes are developed for sea level. Baking at high altitude is such a challenge most recipe developers run from it.
The higher the altitude, the lower the air pressure. The lower air pressure means a rapid rise on every thing. Doesn’t matter if the leavening is from yeast, chemical leavening, or whipped egg whites—the low pressure allows for a must softer cellular structure. So the air bubbles are not as contained.
Water boils at a lower temperature, so baked goods dry out during baking.
These are some of the general guidelines for different baked goods at high altitude. I will say I’ve done very little baking at high altitude. It’s limited to cooking in rented cabins in the mountains on ski and hiking trips. These guidelines are general.
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Yeast doughs
Yeast type: as you witnessed, yeast dough rises at a phenomenal rate at high altitude. Throw in instant yeast and high altitude together and you have a beast beyond control. Use active rise yeast.
Reduce yeast: even with active dry yeast there will be rapid development. So reduce the amount of yeast by 20% - 25%. I would start with 25% less yeast.
Reduce rise time: even with active dry yeast and less of it, the dough will still rise about 25% - 59% faster than at sea level. Check your dough after half the stated rise time in the recipe. Then depending on the development, check every 5 minutes thereafter.
I like to put my yeast dough in a straight sided container. In that way it’s easier to tell how much it has increased in bulk.
Cool temperature: since heat encourages yeast development, try to keep the dough as cool as possible.
Consider chilling your flour for 30 minutes before mixing. In that way the finished dough will cool at the beginning of the rise.
If it is particularly warm in your kitchen, after mixing, place the dough in the refrigerator for about 30 minutes. Then let it finish rising on the counter.
Addition rise: if after changing the type of yeast, reducing the amount of yeast it still grows rapid and wild, add another rise. So if the recipe has two rises, add a third.
Ambient humidity: lower air pressure means dryer air. To keep the dough from drying out, cover the bowl with plastic wrap or a just damp clean tea towel. Make sure the bowl is deep enough so the dough will not come in contact with the plastic/towel as it rises.
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High altitude baking tips for other baked goods.
Low air pressure causes rapid development of leavening bubbles. The increased pressure and rapid expansion can cause the batter to overflow while baking; the gluten structure to fail, and the cake to collapses; sugar to concentrate and prevent batter from setting.
To counter these effects increase oven temperature, decrease baking time and make adjustments to the amount of ingredients.
For all baked goods, adjust oven temperature and they time.
Oven temperature: increase oven temperature by 25°F (15°C).
Baked time: reduce bake time by a third. Begin checking for doneness early.
For ingredient adjustments
begin with reduced amount of leavening and sugar. If the cake still has structural issues, reduce the fat and increase the flour and egg.
Chemical Leavening: reduce leavening by 1/8 - 1/4 tsp per 1 tsp leavening in recipe.
Mechanical leavening: for sponge, angel food, and chiffon cakes, beat egg whites to soft peaks and not firm or stiff peaks stage.
Sugar: reduce sugar by 6 g (1/2 TBSP) - 12 g (1 TBSP) per 125g flour. The higher the altitude, use less sugar.
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Fat: reduce fat by 1/2 tablespoon per 125g flour
Flour: increase flour by 10g per 125g flour in recipe.
Egg: add 1/2 - 1 whole egg per RECIPE. Some bakers only add an extra egg white. But dryness and crumbly texture are common at high altitude. So the extra fat from the yolk may be needed.
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Water boils at a lower temperature at high-altitude. So moisture in baked goods begin to evaporate sooner. If after adjusting your oven temperature and bake time your baked goods are dry, increase the liquid by 15ml - 20ml per 240 ml.
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Macaron: the link below addresses baking macarons at high altitudes. The cookbook authors had pastry chefs test their recipes in high altitude. The adjusted measurements are included, but not the mixing instructions. Since it’s for a French Macarons just use the standard French method.
https://www.lespetitsmacarons.com/high-altitude-baking-tips/
A straight sided container let you better judge the amount of expansion. Even still do the poke test to determine whether or not the dough is ready.