Why Do My Potatoes Go Black After Cooking? | Kitchen Aide

3 weeks ago

Why do immoderate potatoes move achromatic connected cooking, and really do I extremity this happening? I usually time off them to cool successful the cooking water, but should I plunge them in acold h2o instead?”
Jean, Hampshire
“We’ve each been there,” sympathises spud queen Poppy O’Toole. “It’s a harmless chemic reaction,” nan writer of The Potato Book continues, “but it looks rank and only gets worse pinch nan slow cooling process that Jean’s using.” But let’s upwind things backmost for a moment. According to nan nutrient subject guru Harold McGee, successful his book On Food & Cooking, nan darkening of cooked potatoes “is caused by nan operation of robust ions, a phenolic constituent [chlorogenic acid] and oxygen, which respond to shape a pigmented complex”. So what’s nan solution? Make nan pH of nan h2o “distinctly acidic”, which McGee does by adding pick of tartar aliases citrus juice “after nan potatoes are half-cooked”.

Another imaginable fishy for Jean’s blackening tubers is her cookware: “Reactive metals specified arsenic a c alloy weapon aliases aluminium cookware whitethorn besides beryllium nan origin of nan issue,” says the Guardian’s Tom Hunt, which is why he recommends utilizing a non-reactive metallic (think stainless steel) instead. “Leaving nan cooked potatoes successful h2o is besides a bad idea,” adds Jess Murphy, cook patron of Kai Galway successful Ireland and writer of The Kai Cookbook:“They are for illustration small sponges.” Hunt couldn’t work together more: “The potatoes will sorb nan h2o and move soggy and little fluffy – and ne'er refresh them nether acold h2o aliases successful a acold plunge, either, unless it’s momentary.”

Much better, O’Toole says, to drain those cooked spuds, dispersed them retired connected a rack and time off to steam barren pinch a beverage towel complete them. “If you want to beryllium super-prepared, though, you could effort my stiff ready-to-roast potatoes: simply parboil, drain and steam-dry immoderate potatoes, past overgarment them successful melted fat [duck, goose, beef, say], past popular successful nan freezer for roasties connected demand. Otherwise, Hunt would shop immoderate leftover cooked potatoes successful a sealed instrumentality successful nan fridge, but only erstwhile they’ve cooled completely. “You could past move them into crisp murphy cakes to person pinch smoked trout aliases a poached egg,” Murphy suggests. “That’s a elemental but delicious supper.”

More often than not, however, nan discoloration of potatoes happens before cooking, and Murphy wonders if that’s possibly what’s happening chez Jean. Of course, if you’re cooking for a gang, realistically your peeled and trim potatoes will request to beryllium astir for a spot earlier boiling. Oxygen is nan nemesis of nan trim potato, Hunt adds, “so I would support them successful acold water, though that will extremity them turning brownish for only truthful long.” Again, you’ll want to little nan pH level of that water, and Hunt usually adds a driblet of vinegar aliases half a lemon, should he person 1 knocking about.

“At nan restaurant, we ever navigator our potatoes pinch a spot of seaweed,” Murphy adds. “Potatoes are mineral suckers, and by adding seaweed erstwhile boiling, you’re helping to switch those mislaid minerals.” And, that way, you’ll besides request little brackish and adhd much flavour, which is simply a triumph each round.