ATK Reviews

What’s the Best Way to Stir Natural Peanut Butter?

Oil separation is normal with natural peanut butter. We looked for the best (and least-messy) way to stir it.

Published June 23, 2023.

I love natural peanut butter. Conventional creamy peanut butter has its place, and its consistent texture shines in baked goods such as chewy peanut butter cookies. But I can’t resist natural peanut butter’s unadulterated nutty flavor, coarse texture, and runny consistency. 

But natural peanut butter’s biggest drawback is the inevitable oil separation. Each jar requires vigorous stirring; it’s not as simple as opening a jar of Skippy (our favorite creamy peanut butter) and spreading it on a sandwich.

We set out to find the best way to stir natural peanut butter and (hopefully) keep its oils incorporated over time.

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How We Tested

We used three different methods to stir jars of peanut butter: stirring with a knife, stirring with a peanut butter stirrer, and turning the jar upside down for a week.

We tested this on six jars, leaving one jar from each method in the fridge and one at room temperature for a week. 

Before stirring, jars of natural peanut butter have a layer of separated oil.

Method #1: Stirring with a Knife

First, we tried the simplest of tools to stir the peanut butter: a knife. You could use another thin, sturdy tool, such as a jar spatula. Because most jars of natural peanut butter are almost filled to the brim with oil, this method can get messy and oil can splash over the sides if you don’t stir very slowly and carefully.

Patience is the name of the game here. Slowly but surely, it comes together. It took me about a minute and a half. After a week, the room-temperature jar had reseparated a bit. The refrigerated jar was well-incorporated but stiff.

  • Pros: You don’t need to buy an extra tool.
  • Cons: Oil can spill out of the jar, and it takes a while to stir.
  • The Verdict: If you don’t feel like buying a new tool, a knife works just fine. 
Equipment Review

Peanut Butter Mixer

If you hate stirring natural peanut butter by hand, this may be the gadget for you.
Read Our Review

Method #2: Use a Peanut Butter Mixer

You may be wondering, do I need a tool just for mixing peanut butter? You might! This gadget is a simple hand crank attached to a jar lid. You screw it onto your peanut butter jar and stir the crank, mixing the peanut butter while containing any oil splashes.

This method took me one minute to fully mix. After a week, the room-temperature jar had separated about the same amount as the knife method. The refrigerated jar was well-incorporated and a bit more smooth and spreadable, likely due to the oil being well-mixed throughout. 

  • Pros: It contains any spillage and mixes the peanut butter quickly. 
  • Cons: It’s a single-use tool that can take up valuable drawer space.
  • The Verdict: If you want a tool that will minimizes messes and mixes your peanut butter quickly, pick one up.
peanut butter jar comparison
The jar mixed with the peanut butter mixer (left) was a bit more smooth and spreadable than the jar mixed with a knife (right). This photo was taken post-refrigeration.

Method #3: Turn the Jar Upside Down

Since all the oil sits at the top of the peanut butter jar, we wondered if simply flipping the jar upside down and letting it sit would help incorporate the oil with very little effort. Unfortunately, after a week of the jar being upside down, the oil was still completely separated. 

  • Pros: It’s hands-off.
  • Cons: It doesn’t work as a stirring method alone; you’ll still need to stir.
  • The Verdict: A jar stored upside down still requires vigorous mixing before using. 

Does Natural Peanut Butter Need to Be Refrigerated?

With both the knife- and the peanut butter mixer–method, the refrigerated jars stayed better mixed after a week, but they were thicker and less runny than unrefrigerated.

Refrigerated peanut butter (top) stayed better mixed than unrefrigerated (bottom).

Final Results

If you want to minimize messy stirring, it’s worth picking up a peanut butter mixer for about $18.50. A knife will do the trick if you want to avoid buying an extra tool. It works just as well as long as you stir vigorously for at least a minute and a half.

Either way, keeping your natural peanut butter in the fridge will help keep the oil incorporated after stirring. If you prefer a runny, drippy consistency, keep your peanut butter unrefrigerated. 

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