For some, potato salad can be controversial. Different families have their own sacred recipes, and veering from a specific method (like leaving the skin on or failing to add eggs) can be inexcusable. Heaven help the interloper who tinkers with the ingredient list. (You added avocados to Mom’s recipe?!)
Still, most of us agree on one thing: The potatoes ought to be a particular consistency. There’s a certain “just right” quality that J. Kenji López-Alt, a culinary consultant for Serious Eats, describes in his recipe for his classic potato salad.
“Potatoes should not be crunchy or firm,” he writes. “But nor do you want your potato salad to be cold mashed potatoes. The perfect piece of potato should be tender and fluffy all the way through, with the edges just barely beginning to break down, adding a bit of potato flavor to the dressing.”
The Vinegar Trick
In his recipe, López-Alt shares his secret for perfectly cooked potatoes every time: Adding vinegar to the water (specifically, 1 tablespoon of vinegar per 1 quart of water) prevents overcooking.
This one tip has transformed potato salad for Kristina Razon, the Senior Food Editor at Kitchn. Once she tried it, she writes, “my potatoes turned out perfectly — and they have every time since.”
How does this work? The starch in potatoes is held together by pectin. When that pectin breaks down too quickly in the boiling process, mushy potatoes result. Adding vinegar to the water fixes that problem because, as López-Alt explains, “pectin breaks down much more slowly in acidic environments.”
López-Alt uses rice wine vinegar in his recipe, but Razon notes, “I’ve found that white distilled vinegar, white wine vinegar, and apple cider vinegar work well in a pinch.” She does suggest that cooks avoid dark-hued vinegars like balsamic, sherry, and red wine vinegar, “as their stronger flavor will overpower the salad and turn it an unappealing color.”
Other Methods to Prevent Mushiness
There are other ways to guarantee perfectly cooked potatoes, too. These three other guidelines will help you achieve the perfect texture.
To start with, use the right of kind of potato. According to Tasting Table, the best options for potato salad are waxy potatoes — such as red-skinned or fingerling potatoes — which are high in moisture and low in starch. These varieties are most likely to stay intact as opposed to starchier russet potatoes, which are likely to fall apart.
Cut the potatoes into similar-sized cubes or slices so the same cooking time works for all. The smaller you cut them, the higher the risk of overcooking them, so keep an eye on them and drain them when they’re just tender. How long you boil them depends on how big you cut them. The Idaho Potato Commission gives a general guideline of about 8-10 minutes. But if you dice them into 1-inch chunks as they do at Simply Recipes, you will need to cook them for longer — about 20-25 minutes.
Start with cold water, not boiling. According to Love Potatoes, dropping them into cold water instead of boiling water (and letting the potatoes and water heat up together) will prevent the outside from cooking faster than the inside.
As for whether the “perfect recipe” calls for mayo or mustard, we’ll let your family and friends fight that one out.