Standing in the grocery aisle, staring at that bag of Yukon Gold potatoes, what do you think? Will these fit into my recipe? Do I need a hard-skinned variety (for roasting)? Do I need something creamy to mash up?
What matters is versatility (the variety) versus consistency (each potato are different depending on size). Think about it: A big Yukon Gold cooks up more like a russet; a smallish one, more like a new potato. Understanding this difference save you from dry mash or mushy roasts.
Why Potato Size Matters
The chart illustrates what diameter tells you about the texture and where starch settles. Not all of this has to do with weight. A marble-size potato is very dense; it’s a tight little ball of waxiness that won’t fall apart in salad. As the potato gets bigger, it increase its mass. It also takes on more water and starch. By the time it’s at chef size, it will be puffy if you boil it.
So this journey is also telling you what bag to reach for based off serving your meal. Why? Because little ones has a higher skin-to-flesh ratio. Because little ones are mostly just potato-skin. The skin-to-flesh ratio is high.
Those marble and creamer sizes works perfectly roasted whole. You get plenty of crunchy exterior with minimal effort since you don’t have to cut up your spuds. Bigger sizes are best when sliced, wedged, mashed, or any other way where that lower skin percentage would be welcome.
Try to mash tiny new potatoes, for instance and they’ll come out gritty: Their starch hasn’t developed enough yet to make it creamy-smooth. Medium grades, sometimes called A-size, are all-rounders used by a lot of families because they is versatile enough to be peeled and mashed, or just roasted in their skins as wedges. No peeling required when roasting; they’ll mash OK if it comes down to that. Not the best choice for gratin, since thicker slices may break apart or curl up during baking.
Slice the large tuber cleanly to get what you want from a gratin. What is available on the shelf? It depends on seasonal factors. Crops harvested earlier will be small and waxy, while later crops produces large, starchy tubers. An early-harvested potato isn’t as full of starch as if it would of stayed in the ground longer.
Are small winter-bought spuds early new or stored potatoes? Manage your expectations: Examine the texture. Is it firm and dense? They are good for shape-holding. Slightly softer? It may be time for mashing.
Bigger potatoes is better. They contain more reserves inside to help them keep longer in storage, unlike smaller potatoes that tend to be priced higher because they dry out sooner. Larger potatoes is also more economical when buying in bulk. Keep potatoes in a cool, dark place; the bulk bags of bigger potatoes will go farther and store longer.
Buy the biggies if you’re shopping in bulk. The little guys are worth the premium price if they gets cooked right away (convenience food!).
The magic is in picking out the proper size. It turns an otherwise generic ingredient into a useful tool: a thing you cook with intention instead of by guesswork. The size determine whether your finished dish will be a hearty mash or a delicate potato salad. Choose the correct grade, and the rest of recipe takes its cues.