How To Extract Oil From Black Walnuts

You can extract oil from black walnuts by harvesting the nuts, removing the hulls, drying them thoroughly, and then pressing or boiling them to release the oil.
 
Black walnut oil is a prized natural product with a rich, nutty flavor and a long list of traditional uses.
 
If you’ve ever cracked open a black walnut, you know how tough that shell can be, but the rewards inside are well worth the effort.
 
In this post, we’ll walk through the entire process of how to extract oil from black walnuts, step by step, so you can do it at home.
 
Let’s dive into the nuts and bolts of black walnut oil extraction.
 

How to Extract Oil from Black Walnuts

Learning how to extract oil from black walnuts starts with understanding the two main methods: cold pressing and hot extraction.
 
Cold pressing is the traditional, slow way, while hot extraction uses heat and water to speed things up.
 
Both methods work, and the one you choose depends on your tools, your time, and how much oil you need.
 
Here’s how each approach breaks down.
 

1. Harvest and Hull the Black Walnuts

The first step in how to extract oil from black walnuts is gathering the nuts at the right time.
 
Black walnuts are ready in late summer to early fall when the green hulls start turning yellow and soft.
 
Wear gloves because the hulls stain everything they touch with a dark, stubborn dye.
 
Remove the hulls by hand, with a hammer, or by running them over a rough surface.
 
Once hulled, rinse the nuts and spread them out to dry.
 

2. Dry and Crack the Shells

Drying is critical if you want to know how to extract oil from black walnuts properly.
 
Let the nuts air-dry for two to three weeks in a cool, ventilated spot until the shells feel hard and light.
 
Then crack the shells with a hammer or a heavy-duty nutcracker and pick out the nutmeats.
 
Be patient here, as black walnut shells are famously tough.
 
The better you separate the nutmeats from the shells, the cleaner your oil will be.
 

3. Grind the Nutmeats Into a Paste

Now that your nutmeats are ready, grind them into a fine paste using a blender or food processor.
 
The finer the paste, the more oil you’ll be able to extract from black walnuts.
 
A coarse grind leaves oil trapped inside, so take your time with this step.
 
You can also crush them with a mortar and pestle if you’re working in small batches.
 

Cold Pressing Black Walnuts for Oil

Cold pressing is the gentlest way to extract oil from black walnuts, and it preserves the most flavor.
 
Here’s how the cold-press method works.
 

1. Wrap the Paste in Cheesecloth

Scoop your black walnut paste onto a piece of cheesecloth and tie it into a tight bundle.
 
This bundle is what you’ll squeeze to release the oil.
 

2. Apply Slow, Steady Pressure

Using a manual press or even strong hands, squeeze the bundle over a bowl to collect the oil.
 
Slow, steady pressure gets more oil out than quick, hard squeezes.
 
Keep going until the paste stops releasing oil.
 

3. Strain and Store the Oil

Pour the collected oil through a fine mesh strainer or coffee filter to remove any bits.
 
Transfer the clean oil into a dark glass bottle and store it in a cool, dark place.
 

Hot Extraction Method for Black Walnut Oil

If you want to extract oil from black walnuts faster, the hot method is your friend.
 
This approach uses heat and water to pull the oil out of the paste.
 

1. Simmer the Paste in Water

Place your black walnut paste in a pot, cover it with water, and bring it to a gentle simmer.
 
As it heats, the oil rises to the surface.
 

2. Skim the Oil Off the Top

Use a spoon or ladle to skim the floating oil into a separate container.
 
Keep simmering and skimming until no more oil appears.
 

3. Cool, Strain, and Bottle

Let the collected oil cool, then strain it through a fine filter.
 
Bottle it up, and you’ve successfully learned how to extract oil from black walnuts using heat.
 

So, How Do You Extract Oil from Black Walnuts?

You can extract oil from black walnuts by hulling, drying, cracking, grinding, and then pressing or simmering the nutmeats to release their oil.
 
Whether you choose cold pressing or hot extraction, the key is patience and clean preparation.
 
Both methods let you extract oil from black walnuts that’s rich, fragrant, and full of character.
 
Give it a try this harvest season and enjoy the fruits of your labor.