How to Make Peanut Butter Harden

Things You'll Need

  • Refrigerator

  • Peanut butter with hydrogenated vegetable oil

  • Waxed paper

  • Cookie sheet

Stock your refrigerator with celery and hardened peanut butter for a fast snack.

Whether you want to roll your peanut butter into spheres or you're storing peanut butter-topped fruits in the fridge, hardening your peanut butter contains the spread and minimizes the mess. Fortunately, peanut butter producers create this nutty and nutritious spread with smoothness and congealing in mind. During the manufacturing process, companies crush and heat peanuts to over 160 degrees Fahrenheit before mixing a small amount of hydrogenated vegetable oil throughout the peanut butter. The hydrogenated vegetable oil hardens, stabilizing the peanut butter as it cools in the jar and preventing the peanut oil from forming an oily layer on the surface.

Step 1

Mix your peanut butter with whichever ingredients the recipe calls for, such as sugar, butter or flour.

Step 2

Shape or spread your peanut butter in the position you want it to harden. Spread the peanut butter on the bottom of a paper candy cup or pan to make peanut butter cups. Place balls onto a waxed paper-covered cookie sheet or dish if you are making peanut butter balls. Insert any toothpicks or decorations at this time, while the peanut butter is still soft.

Step 3

Place your pan, sheet or plate inside the refrigerator or freezer. Place the platter in the freezer for an hour to create rock-hard peanut butter or store the plate in the refrigerator for 45 minutes for a firm to slightly hard consistency.


Don't try to make balls from peanut butter unless directed to do so by the recipe. Molding traditional commercial peanut butter without additional ingredients, like butter or grain, is nearly impossible.

Peanut butter softens quickly, so serve your hardened peanut butter treats immediately after removing them from the freezer.


Avoid using organic peanut butter unless specifically directed by the recipe. The lack of any stabilizing ingredients makes organic peanut butter more difficult to ball or spread.