Why Is Peanut Butter So Hard to Swallow?

And more on the science of this childhood staple.
By and

Published Aug. 12, 2022.

Peanut butter was a staple food group for me growing up. I would spread it on a morning English muffin, eat a PB&J for lunch at school, and if everything went according to plan, end the day with a peanut butter cup or two or three or four. 

There was only one problem with my all-peanut butter diet: I spent a lot of time as a kid trying to get peanut butter unstuck from the roof of my mouth. 

Have you ever wondered why peanut butter is so hard to swallow? To find out, read on: And check out the latest episode of my web series, What’s Eating Dan?, for even more peanut butter science.

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Why Peanut Butter Is So Hard to Swallow

When you put a spoonful of peanut butter in your mouth, it gets increasingly thick, clingy, and difficult to swallow. Why? The proteins in peanut butter absorb water and swell. 

To see this effect at work, I conducted a simple experiment: I made a batch of homemade peanut butter and split it into 2 samples. To one, I added two teaspoons of oil, which thinned it right out (the proteins in peanut butter don’t absorb oil). To the other, I stirred in one teaspoon of water. Sure enough the butter transformed from runny to thick.

As you chew a bite of peanut butter, the same effect is at work: Its proteins absorb the water from your mouth and the peanut butter becomes more difficult to swallow.

How to Make Your Own Peanut Butter

You can use this protein know-how to perfectly dial in the texture of homemade peanut butter to fit your taste. Here’s how to do it.

1. Roast raw peanuts in a 375 degree oven until fragrant and slightly darkened.

2. Process the peanuts until the oil is released and a paste begins to form.

3. Add a touch of honey and salt and process again.

4. Customize your texture: Add water for thicker butter, or oil for thinner.

Get the full recipe for Homemade Peanut Butter here

Nutty for peanut butter? Learn more in the latest episode of What’s Eating Dan?.

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Peanut Butter–Banana Muffins

Want to use up those overripe bananas? In less than an hour, you can turn that dark-speckled bunch into impressively tall, fluffy, fruit-packed muffins.
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