Baked, mashed, boiled, fried – in a general sense, it's hard to do potatoes wrong. There's something about the fluffiness of a well-baked potato, the crunch of a nice chip, the creaminess of mash (the best recipe I know: keep adding butter until it stops being absorbed) that warms the heart, as well as the taste buds.
But if you've ever chosen the wrong potato for the job, chances are you know it. It may not be the kind of thing explained to you in school, but anyone who's tried to fry red potatoes or make salad with russets knows, not all spuds are created equal. Some of them – to put this mildly, as my smoke detector did not – are not meant for frying.
There are hundreds of different breeds of potatoes, and it turns out that beneath that yellow or brown or purple or red skin, they have quite different chemistries. Potato breeders and food scientists divide them up into broad categories, usually mealy and waxy. Mealy (or sometimes “floury” or “starchy”) potatoes are dry, fluffy, and a little grainy when cooked; they are a relatively high 22% starch by weight, according to research by Diane McComber cited in this piece by food scientist Guy Crosby.