xkcd #3187: High Altitude Cooking Instructions
Title text:
1,300,000-1,400,000 ft: Ask a crew member to show you how to use the ISS food warmer.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3187/
I used to live at 3300 feet. Cooking times increased slightly over what most recipes recommended, sometimes more baking powder was needed, but I don't remember having to add more water.
The higher altitude, the lower the atmospheric pressure, and the lower the boiling point of water. At 3300, you were down to 207°f. I used to work at a restaurant at 8k feet and we were down to a boiling point of 195, which was enough to make things like, say brownies, noticeable dryer if you didnt compensate for the extra water boiling off durrong cooking.
We actually had a fancy oven for pastry that you could set the pressure inside of, allowing us to cook things as though at sea level.
207°f
I don't know how much that is in the Boiling Water system
Meant to leave that context for for our metric friends, but my post was getting long so I shortened it. In Fahrenheit, water boils at 212°f and freezes at 32 at 1 atmosphere. (Sea level) the conversion rate is 1.8°f=°c (after subtracting those 32 'extra' degrees)
So at 207, his boiling point is only 5°f (3.33°c) lower than at sea level. Whereas where i was cooking, it was closer to 10°c - enough to considerably dry out anything baking for a decent amount of time, and throw a lot of baking chemistry off (anything leavening with baking soda, etc changes, and breads risk colapsing although that's less about the h2o, and more about the pressure iirc)
97°c
7k here, I really need to invest in a pressure cooker.
The extra cooking time results in more water loss. I'd imagine in most recipes it'd be nearly imperceptible.
Definitely not as much as half a cup.
Wouldn't it depend on how many cups the original recipe calls for?
I wonder if it's assuming you don't use a slightly lower heat output though despite the lower boiling point?
If you're cooking something at altitude you shouldn't lower the heat - you still need to cook it properly.
Boiling water is a fixed temperature at a given air pressure. Turning up the heat doesn't make the water hotter. You just lose it faster. If you need higher temperatures and are cooking in boiling water, then you have to use a pressure cooker.
Who said anything about turning the heat UP?
I meant up relative to the boiling point. Since the boiling point is lower, the same heat output is relatively higher. It just boils the water faster and does nothing to the temperature. You just need enough heat to get it to a boil if you don't want to waste extra water and heat.
The pressure difference doesn't change how many joules of energy needs to enter the food to cook it.
But it does change how much power you need to use. If you leave the power the same, you'll need more joules because you need more time and are sending more of it to the atmosphere.
Baking mostly, it's a cruel and fickle mistress
I'm not sure if it's still the case but most of the population in Mexico is above 3000 feet so recipes had variations for sea level instead (the recipe was made for 1000msnm)
Sometimes it was confusing if you got something imported from the US or some brand that needed to be adjusted for high altitude
surprised it's not to be cooked with re-entry heating.
There really is an xkcd for everything.
You could also just use a pressure cooker
A community for a webcomic of romance, sarcasm, math, and language.