Oily Coffee Beans: Why They Are So Bad For Coffee Grinders?

When I was a beginner homebrewer, I was not aware that oily coffee beans could ruin my coffee grinder.

I proceeded to grind my oh-so-shiny beans as I thought the gloss was a sign of high-quality beans. The next thing I know, my coffee grinder was done for.

Even worse, I also found out that oily beans can ruin my other coffee-making tools. To help you prevent the same thing from happening to your tools, let me discuss why oily beans are a big no for your coffee grinders.

Why Are Some Coffee Beans Oily?

oily coffee beans
Oily coffee beans are a result of a long roasting process and air exposure.

Coffee beans are seeds of coffee cherries. Farmers harvest the coffee cherries and dry them under the sun until most of the moisture evaporates.

Once the coffee beans dry, all that remains in them are the sugars and oils. The oils contain the majority of flavours and caffeine.

The oils remain in the coffee beans until the roasting process. As the heat dries out the coffee beans further, they will crack, causing the oils to release into the surface.

The amount of oil that the beans lose depend on the beans’ roast level. A dark roast releases most of the oils, causing them to coat the beans and making them glossy.

That said, one of the significant reasons for oily coffee beans is that they were roasted for a long time. The fresher these beans are, the more oil coating they have.

Oily coffee beans are also a result of letting them sit for a long time. As you leave the beans unused, they gradually release oils, causing them to become shiny and more aromatic.

Why Are Oily Coffee Beans Bad For Coffee Grinders?

oily coffee beans
Oily coffee beans can clog and ruin your coffee grinder.

True enough, oily beans mean more flavour and aroma. However, the same thing that makes coffee beans great can also end the life of a coffee grinder.

Speaking from experience, you should really avoid grinding oily coffee beans unless you want to end up as someone who broke their favorite coffee grinder!

To help you avoid such a dilemma, below are the reasons why oily beans are a big no-no for coffee grinders.

1. Oil makes the bean hopper sticky.

The residual oil that came from your coffee beans will cling to the different parts of your grinder, especially the bean hopper. Since oil is sticky, it will hold some of the beans on the sides of the bean hopper.

As a result, the coffee beans will not flow within the grinder, preventing you from getting the coffee grounds you need.

2. Oily coffee beans clog grinders.

Coffee bean oils make coffee grounds sticky. The grounds stick together and cause your coffee grinder to clog.

Oily beans also cause buildups on all parts of your grinder. This residual oil will become sticky after consistent usage, which can impact the taste of your coffee grounds.

oily coffee beans

3. Oily beans are difficult to grind.

The stickiness of oils in the coffee beans makes them challenging to grind. Once the coffee beans release oils and stick together in the bean hopper, your grinder continuously spins without pounding the beans.

Since the grinder is constantly spinning without grinding anything, it could collapse, thus rendering it useless.

How To Dry Oily Coffee Beans

oily coffee beans
Salt and paper towels can absorb some of the oil from the coffee beans.

Oil is a natural part of coffee beans. Once dry coffee beans are exposed to the air, they will oxidize, causing the oils to cover the beans’ surface.

Fortunately, you can transfer coffee bean oils into something else to make your coffee beans grinder-friendly.

Preventing oxidation

Oxidation happens when you expose coffee beans to the air. To prevent beans from oxidizing further, you need to store them in an airtight container.

Then, place the container somewhere dark. This way, coffee beans will not release any more oil.

Transfer the oil to an absorbing medium

Before grinding your oily coffee beans, you can pat them dry with a paper towel to absorb the oil on the surface. You can also do this step before placing your coffee beans in a container.

If you see that the paper towels have become greasy, replace them with new ones. Continue to replace the paper towels until they no longer absorb oil from the beans.

oily coffee beans
Keeping coffee beans in an airtight container prevents it from oxidizing and excreting more oil.

Using salt for oily beans

Salt can soak up grease and oil, making it ideal for oily coffee beans. All you need to do is to cover the bottom of your container with salt before adding the coffee beans and then spread the beans evenly on top of it.

Then, cover the coffee beans with salt before closing the container.

Leave the coffee beans in the salt for at least an hour. If the salt becomes greasy, then it has absorbed the oil.

If the coffee beans still have some oil on their surface, let them sit in the salt for another hour.

Finally, get the beans out of the salt and toss them on a plate to remove the salt stuck on their surface.

What To Do With Oily Coffee Beans

oily coffee beans
Oily coffee beans are ideal for cold brewing.

It is not ideal to grind greasy coffee beans as they can ruin your coffee grinder. Fortunately, you can remove some of the oil using the methods mentioned above.

But if you do not have time for such hacks, there are other ways that you can brew such beans to make excellent-tasting coffee.

Grind the beans coarsely.

Oily and dark coffee beans will release less oil if you grind them coarsely. The grind size will allow you to extract the beans’ rich flavours and chocolate notes.

Even better, brewing coarsely ground coffee beans will help you avoid strong and bitter notes from releasing into your coffee.

Use the cold brew method.

Oily coffee beans are perfect for cold-brewed coffee. The reason is that using room temperature water to steep coffee grounds will prevent them from releasing oil.

Cold brewing can also extract the malty and sweet flavours from your coffee grounds. Additionally, this brewing method is very forgiving, allowing you to make good coffee despite the quality of your coffee beans.

Brew the beans at a lower temperature

Cold-brew needs to steep for 18 to 24 hours before you can enjoy it. If you cannot wait for such a long time, you can instead use hot water to brew your oily beans.

The average temperature for brewing coffee is 205 degrees Fahrenheit. But if you are brewing oily coffee beans, the recommended water temperature is 195 degrees Fahrenheit.

The lower water temperature will help you reduce the amount of oil and harsh flavours from your coffee beans.

Frequently Asked Questions

oily coffee beans
Some people think that oily coffee beans are fresh, but the truth is that they taste stale and burnt.

Why is Starbucks coffee so oily?

Starbucks is popular for using dark roasted coffee beans in its coffee blends. As mentioned, the darker your beans are, the more oil they excrete.

If you buy whole coffee beans from Starbucks, you will notice that each bean is glossy and covered with oil.

What coffee beans are less oily?

If you do not like oily beans, the ideal thing is to buy light or medium roast beans. A lighter roast means less oxidation and less oil released by the beans.

However, it is essential to note that light and medium roast coffee beans will have a milder flavour than dark roast beans. So, they may not be ideal for people who like their coffee bold and strong.

How do oily coffee beans taste?

There is a common misconception that oily beans mean fresh beans. Such is not true at all.

Oily beans are stale and taste burnt since they have been roasted for a long time. They also have a harsh and bitter flavour, especially when brewed at a high temperature.

The Bottom Line

oily coffee beans

Oily coffee beans can be the primary cause of coffee grinder breakage. Due to their oil content, coffee grounds stick together, resulting in a clogged grinder.

When worse comes worst, oily beans will cause various issues until your coffee grinder collapses.

Fortunately, you can use paper towels and salt to absorb some of the oil from your coffee beans before grinding them. Both the paper towels and salt are highly absorbent, so they will work on your greasy beans.

But if you do not have the time to remove oil from your beans, the best thing to do is to use light to medium roast beans.

You can also grind your oily beans coarsely to prevent them from releasing too much oil. Additionally, the best brewing method for oily beans is cold brew, as it prevents the oil from coming out of the beans.