In the world of specialty coffee, baristas often use a variety of creative techniques to enhance flavor and texture. One of the more well-known methods I’ve shared before is milk-washing—a fascinating process that clarifies milk and transforms both its texture and taste.
But milk-washing isn’t the only trick in our toolkit. There are many other methods that bring out unique and complex flavors in coffee. Today, I want to introduce you to one that’s similar in principle but completely different in character—oil-washing.
If you spend any time on social media lately, you’ve probably come across “oil-washed coffee.” As the name suggests, it’s a type of coffee infused or treated with oil. I started experimenting with this technique quite a while ago, and both the process and the results are truly one of a kind. Many people have asked me about it recently, so let’s dive right in—what exactly is oil-washing, and how can we make oil-washed coffee at home?
What Is Oil-Washing?
Oil-washing—sometimes called fat-washing—is a culinary technique that uses the difference in freezing points between oil and other liquids to extract flavors from fats into another medium.
Like many crossover techniques in coffee, it originated in the world of mixology. In 2007, a New York cocktail bar pioneered the method by infusing spirits with the aroma of oils and fats. The results were so impressive that fat-washing quickly became popular across the cocktail scene.
Interestingly, the roots of this technique trace even further back—to an 18th-century process known as enfleurage, which was originally used in perfumery to extract floral scents using fats.
When it comes to ingredients, there are virtually no restrictions, aside from two basics: they must be edible and non-toxic. You can use any kind of fat—from plant-based oils and nut butters to animal fats like butter or lard. Likewise, the items being infused can range from liquids like coffee and spirits to solid ingredients like spices, fruits, herbs, or citrus peels. The goal is simple: extract the aroma and flavor from one medium into another.
How Does Oil-Washing Work?
The process is surprisingly straightforward and involves just three steps:
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Combine the ingredients thoroughly.
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Refrigerate the mixture for several hours.
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Filter out the solidified fat to obtain a clear, fragrant liquid.
The principle behind this is that fats solidify at higher temperatures than most liquids. As the temperature drops, the fat congeals first. By removing it before the rest of the mixture freezes, you’re left with a clean, clarified liquid rich in the fat’s aroma and subtle flavor notes.
When making oil-washed coffee, the ratio of oil to coffee depends on the desired flavor intensity and the specific ingredients used. There’s no universal formula—it’s all about experimentation and personal taste.
Before we jump into the recipe, though, there are a few important things to note to ensure a smooth (and delicious) experience.
Things to Know Before You Start
First, when you see “oil-washed coffee” in cafés, note that not all of them wash the coffee itself. Some wash spirits with oil first and then mix those infused liquors into coffee-based drinks. Keep an open mind—the method is flexible.
Second, temperature matters. Many online recipes show “coconut oil-washed cold brew,” but using cold brew directly often leads to an unappealing, lumpy mixture. That’s because the oil solidifies instantly in contact with the cold liquid. To avoid this, use warm coffee or heat your cold brew slightly before mixing.
Third, not all fats start in liquid form. For example, butter remains solid at room temperature, so it needs to be melted before use. You can do this by heating it directly or allowing it to melt in contact with hot coffee. Only when the fat is fully liquid can it release its aromatic compounds effectively.
How to Make Oil-Washed Coffee
Now that we’ve covered the theory, let’s get hands-on.
For this batch, I used a dark-roasted Sumatra PWN Golden Mandheling coffee, paired with butter as the fat source. My goal was to create a rich, full-bodied cup with a gentle buttery aroma.
I used a 1:6 ratio of butter to coffee—strong enough to carry the aroma but not so heavy that it overpowers the coffee’s character.
Here were my brewing parameters:
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Coffee dose: 15g
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Brew ratio: 1:15 (coffee to water)
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Grind size: similar to fine sugar (75% pass through a 20-mesh sieve)
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Water temperature: 89°C (192°F)
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Brew time: 2 minutes
If you’re using hot coffee, you can add the butter directly into your server before brewing. The heat from the brew will melt the butter naturally.
Once brewing is complete, mix the coffee and melted butter thoroughly. If you have a milk frother or blender, that’s ideal. Otherwise, pour the mixture into a sealed jar and shake vigorously for several minutes. (Note: if using hot coffee, let it cool to room temperature before shaking to avoid accidents.)
After mixing, seal the jar and refrigerate for at least 2 hours—I usually leave mine overnight. When the fat has completely solidified, filter the liquid through a paper filter or several filter cones. This can take a while, but patience pays off.
And there you have it—a clear, aromatic oil-washed coffee!
The Taste Experience
At first glance, the drink might look like an ordinary cup of coffee, but the flavor tells a different story. The butter softens the bitterness and adds a velvety texture. Despite being a dark roast, the cup tastes smooth and balanced, with hints of spice, chocolate, and a gentle buttery note on the finish.
I also made a coconut oil-washed cold brew using a 1:4 ratio of oil to coffee to amplify the coconut aroma and emphasize the cold brew’s natural concentration. The result? A richer, more layered cup—sweet, mellow, and luxuriously creamy.
Interestingly, the leftover solidified fat that you filter out is now infused with coffee aroma. Don’t throw it away—it can be used for cooking or baking to add a subtle coffee twist to your dishes.
Final Thoughts
That’s everything you need to know about making oil-washed coffee. It’s simple, creative, and endlessly customizable. Just be careful during the mixing stage—things can get messy fast!
Give it a try at home, experiment with different oils and beans, and discover your favorite combination. Sometimes, the most surprising flavors come from the most unexpected techniques.