If there is a starch that rules the American table, it is the potato. They go with almost any main dish, and are the very picture of versatility—you can, as Master Samwise puts it, “boil ’em, mash ’em, stick ’em in a stew.” If you’ve followed this blog for long, you already know about our love for hot, golden, crispy fries.
But given how common potatoes are in our diet, people know relatively little about them, especially the ways that they interact with temperature. Here, we’ll give you all the dirt on potatoes, from types to temps and beyond. Let’s get serious about spuds!
The potato is a member of the nightshade family (related to tomatoes, chilies, and tobacco) and was originally native to the northern reaches of South America. It is a tuber that grows on the roots of the plant, acting as nutrient storage for the plant. There are thousands of cultivars of potato and they are now eaten across the globe. In fact, the potato is the world’s largest vegetable crop.
Potatoes are quite rich in vitamin C and potassium (with more potassium than bananas!). They are also chock-full of energy. There is a reason the peasants of Europe took up the potato with such fervor once it was introduced to the continent. A vegetable that is easy to grow, hardy, and inexpensive, that also prevents scurvy while providing energy for a full day of field labor? Yes, please!
If that sounds like a golden food, then you’re paying good attention. It is not, however, perfect. As a member of the nightshade (solanum) family, the plant has developed certain defenses against pests. They can contain high levels of the toxic alkaloids solanine and chaconine. These bitter compounds form in the potato when they are exposed to light or when they experience stress while growing. Because potatoes also turn green when exposed to too much light, a green hue can be a sign that potatoes have been exposed to too much light and could, therefore, have more toxins than you should eat. When you encounter green potatoes, either discard them or peel them deeply, past the green. Or if your potatoes taste very bitter, don’t eat them. They could be toxic.
If it pierces the center easily and meets no resistance, your baked beauties are ready to serve. You can also use an instant-read thermometer; inserted into the center of the potato, the temperature should read 208-211˚F.
Mealy vs waxy potatoes: what’s the difference?
There are two main divisions within the potato kingdom: mealy vs waxy potatoes. Mealy potatoes, which cook up with a “drier” texture that is more finely textured, concentrate more dry starches in their cells. This also makes them quite dense. Because of their drier, fluffier cooked texture, they are excellent for making fries, baked potatoes, and mashed potatoes. They can absorb cream and butter more readily, making the finished mash rich and luscious. The cells in these potatoes tend to break apart more readily, practically disintegrating in boiled dishes if not treated properly. This tendency to disintegrate makes mealy potatoes a less-than-ideal choice for some casseroles and gratins.
Waxy types, however, carry less starch and cook up with a “wetter” texture. Their lower starch-content also means that they hold their shape better—there are fewer starch granules that will burst and expand, throwing cell pieces hither and yon. They are ideal for the gratins and casseroles but cook up as soggy fries and heavy mashed potatoes. Still, they are some of my favorites for many applications.
Whether you use waxy potatoes or mealy, the physical changes that need to happen are the same: starch granules need to swell and burst, a process which happens beginning at 137–150°F (58–66°C). But that’s only where it starts. To soften the starches and improve the texture, you really want to get as close to water’s boiling point as you can.
Think of when you add starch to a sauce. The sauce stays thin until you approach the boil, and only then does the sauce thicken. That’s because of the starch gelation at that point. We want the same thing in our potatoes, but instead of getting thicker, the potato flesh gets softer, less chalky, and far more appetizing. The closer you can get your potatoes to the boiling point, the better.
To test this idea, we cooked several potatoes in our demo kitchen and studied the results. We used yellow, red, russet, and sweet potatoes and inserted probes into the center of each one. We boiled two of each kind and baked two of each kind, setting the corresponding ChefAlarms for 190°F (88°C) and 210°F (99°C) (based on the advice of some potato experts we contacted). It was only after setting the high alarms and bringing our water to a boil that we realized a problem: we can’t boil water up to 210°F (99°C) at this elevation! Our water boils at about 204°F (96°C) up here in the Mountain West, so there’s no hope of boiling a potato to 210°F (99°C)!
We adjusted our goals, aiming for 202°F (94°C), the same distance below the sea-level boil as the suggested temperature.
Why not just set the target for the boiling point itself? Thermodynamics. The closer the temperature of an object gets to the ambient temperature, the longer it takes to heat up. Heat exchange slows down drastically. So cooking all the way to the boiling point tacks on significant time. Plus, starch gelation is an endothermic process, so the potatoes are actually sucking heat out of the probes as the starches loosen and abandon their crystalline state. Actually reaching the boiling point is not easy.
How to store potatoes: temperature matters
Those temps are quite cool without being cold, and explain how farmers used to get through the cold months when nothing was being harvested—fresh taters all winter long in the root cellar!
Many basements run at a cool temp. To know if your cellar is optimal for spud storage, stick a ChefAlarm® with a probe in there and let it come to temperature. Then clear the min/max function and let it sit for a day or so. Read the minimum and maximum temps encountered and you can easily see how well suited your basement is for root-cellaring your potatoes. The closer you can keep your potatoes to that optimal temp of 45–50°F (7–10°C), the better.
Smoked Baked Potato Internal Temperature
FAQ
What is normal body temperature for a potato?
What temp should I probe potatoes?
What is the minimum hot temp for potatoes?
What temperature should a potato be cooked at?
We recommend baking potatoes at high temperatures of 400-450 degrees F. As potatoes take a long time to cook, lower temperatures will take much longer to cook. When the center of a potato reaches 210°F (100°C), your potato is done cooking. In fact, 205°F out of the oven is closely enough, since it will keep rising while resting.
What is the water content of potatoes?
It varies on the variety of potatoes but in general, raw potatoes contain approximately 75% to 80% water. The cooking method and ingredients used to cook potatoes will affect the final water content of the potatoes.
What temperature should a potato be in a thermometer?
If you are still feeling unsure, use an instant-read thermometer: their internal temperature should be between 208°F and 211°F. (In this magic temperature zone, starch granules in the potato have absorbed water, ruptured, and rendered the interior flesh fluffy and light.)
Why is 205 degrees a good temperature to cook potatoes?
Here’s why 205 degrees is ideal: Cooked to that temperature, the potatoes’ starch granules were able to absorb much of the interior moisture, swelling and causing the cell walls surrounding the granules to separate into clumps that result in a texture we perceive as dry and cottony.