would in the open air Most pressure cookers allow you to cook at temperatures between 240° and 250°F, no matter what the altitude This is why pressure cookers are so popular throughout the Andes—no self-respecting Colombian home is without one WATER-BOILING MYTHS M yths about boiling water abound Here are four of the most common: • Cold water comes to a boil faster than hot water False It’s absolutely untrue, but there is a good reason to use cold water instead of hot for cooking: hot water will contain more dissolved minerals from your pipes, which can give your food an off flavor • Water that’s been frozen or previously boiled will come to a boil faster False, though there is a little scientific reasoning behind this one Boiling or freezing water removes dissolved gases (mostly oxygen), which can slightly affect the boiling temperature—so slightly, in fact, that neither my timer nor my thermometer could detect any difference • Salt raises the boiling point of water True sort of Dissolved solids like salt and sugar will in fact increase the boiling point of water, causing it to come to a boil more slowly, but the effect is minimal (the amounts normally used in cooking effect less than a 1-degree change) For it to make any significant difference, you’d need to add it in really vast quantities So for the most part, you can ignore this one • A watched pot never boils Definitely true Avert your eyes On Salt and Nucleation So, if salt doesn’t lower the boiling point of water, how come throwing a handful of salt into a simmering pot will cause a sudden eruption of bubbles? It’s because of tiny things called nucleation sites, which are, essentially, the birthplace of bubbles In order for bubbles of steam to form, there has to be some sort of irregularity within the volume of water—microscopic scratches on the inside surface of the pot will do, as will tiny bits of dust or the pores of a wooden spoon A handful of salt rapidly introduces thousands of nucleation sites, making it very easy for bubbles to form and escape The same principle is used to “seed” clouds Releasing dusty particles from an airplane causes millions of nucleation sites to be created in the moist atmosphere so water vapor droplets can coalesce and form clouds ... Dissolved solids like salt and sugar will in fact increase the boiling point of water, causing it to come to a boil more slowly, but the effect is minimal (the amounts normally used in cooking effect less than a 1-degree... essentially, the birthplace of bubbles In order for bubbles of steam to form, there has to be some sort of irregularity within the volume of water—microscopic scratches on the inside surface of the pot will do, as will tiny bits of dust or... vast quantities So for the most part, you can ignore this one • A watched pot never boils Definitely true Avert your eyes On Salt and Nucleation So, if salt doesn’t lower the boiling point of