Mayo Is The Powerhouse Ingredient For Crispy Roasted Potatoes

French fries, hash browns, and potato chips are proof that many roads lead to crispy potatoes. But whether you start by grating them or slicing them, frying potatoes is normally the key step. On the other hand when you roast them in the oven, there's always a chance you could end up with potatoes that are either too soggy or too dry. That's where mayonnaise comes in.

There are two factors that cause potatoes to crisp up. The first is the composition of a potato. Potatoes are made of starch, and when potatoes cook, their cells lose moisture. In the absence of moisture they become crispy. The addition of fat facilitates this process, which is why frying potatoes, as opposed to baking them in the oven, usually yields crispier potatoes. 

The more fat present, the hotter the surface of the potato will get, and the more effectively it'll brown. Oil and butter can easily accomplish this, but mayonnaise can do it better.

What mayo does that oil can't

Slathering your potatoes in mayonnaise may seem off-putting, especially if you're not a huge fan of the condiment. But there's a good reason you should use it over oil. While oil causes potatoes to brown in only one way — by bringing the temperature up — mayonnaise causes it to brown in two ways. 

In addition to facilitating thermal browning, mayonnaise also triggers the Maillard reaction, which occurs when proteins, sugar, and heat are combined. Because mayonnaise is made up of an emulsion of egg and vinegar, with the addition of heat, it has all of the factors necessary to produce the chemical reaction.

Mayonnaise's smoke point also plays a role in the crispiness of a potato. A higher smoke point allows you to leave the potatoes in the oven to brown longer without risking them burning. Whereas vegetable oil has a smoke point of about 400 degrees Fahrenheit, mayonnaise's is closer to 450, making it more effective for roasting potatoes.

How much mayonnaise should you add to roasted potatoes?

Because mayonnaise is just a combination of oil, vinegar, and eggs, its distinct flavor dissipates when it gets cooked in the oven. Going overboard with mayonnaise, therefore, won't affect the flavor of your roasted potatoes. However, it may affect the texture. Potato starch has absorbent qualities, and too much mayo could make your potatoes greasy. Use the same amount as you would oil, and this shouldn't be an issue.

For best results, you'll also want to add the mayonnaise at a strategic time. AllRecipes recommends coating your potatoes with mayonnaise only after their temperature reaches 205 degrees, then continuing to bake them for another 10 minutes. 

@eitan

Mayo Roasted Potatoes are going to be your new favorite cooking hack this season! cooking food chef

♬ original sound – Eitan Bernath

Or, as chef and culinary influencer Eitan Bernath highlighted in a viral TikTok, you can also add the mayonnaise before you put them in the oven. Either way, you'll end up with potatoes that are a lot crispier than if you were to use oil.