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When you’re in the market for good coffee, you may have noticed that some coffee beans are more “oily” than others.

But what is the real reason behind the oiliness of some coffee beans? Does it change the taste of your coffee?

In this article, we’ll break down why is your coffee beans oily, as well as the impact that oiliness has on the flavor of your coffee.

From the effects of the coffee roasting process to the type of coffee bean used, we’ll examine the various factors that contribute to the oily sheen of coffee beans.

Some Common Reasons Behind the Oiliness of Coffee Beans

Coffee beans are the seeds of a fruit, and like other fruits, their appearance can vary from one variety to another.

Whether the coffee beans are oily or not is determined by their variety, their growing conditions, and the roasting process.

Naturally Oily Coffee Bean

Different varieties of coffee beans have different levels of oiliness. For example, Arabica beans are more oily than Robusta beans.

This is because Arabica beans are grown in higher altitudes, where the air is cooler and drier. This environment results in less oil production in the beans.

Coffee Beans Roast Level

When coffee bean is harvested, farmers cover them in a protective layer of surface oil. This layer of oil helps protect the bean from the elements while processing, and the coating also helps to preserve the flavor of the green coffee bean.

As the green oily coffee beans are roasted, the oil is cooked off, leaving the bean dry and crunchy (initially).

However, coffee beans contain oils inside them where all the flavors, amino acids, antioxidants, and caffeine contents reside. This coffee oil starts coming out as it is roasted from the endosperm to the surface of the coffee bean.

Dark roast beans tend to be more oily than light or medium roast beans, as the higher temperatures and long roasting times cause more oil to be released from the beans.

Dark Roast vs Dark Beans

When it comes to dark beans, the oils are not released during the roasting process, but rather during the brewing process.

The oils in dark coffee beans are released when the beans are ground and exposed to hot water, which causes them to “bloom” and release their oils.

The oils in dark beans are what give them their deep, rich flavor.

Processing Techniques

How the coffee roasters process beans can also affect the level of oiliness in coffee beans.

Wet-processed coffee beans, for example, tend to be oilier beans than dry-processed beans, as the wet-processing method leaves more of the oils intact.

Storage Conditions

Coffee beans that are stored in warm, humid environments will release more oils, according to a study on Molecules Journal, resulting in oily coffee beans.

Also, the oils in your coffee bean will begin to leak if they have been stored on a shelf at the store for a long period. This is why we suggest buying recently roasted coffee.

The Chemistry Behind Oily Coffee Beans

Oily coffee beans are the result of the coffee roasting process, and the chemistry behind it is fascinating.

When coffee beans are roasted, the bean’s outer layers undergo a chemical reaction called Maillard Reactions.

This reaction occurs when the heat from the roaster causes the proteins and sugars present in the bean to break down, forming new compounds and producing the characteristic aroma and flavor of the coffee roasts.

During the roasting process, oils are released from dark roast coffee beans, which is what gives coffee beans their trademark oily texture.

The oils are composed of triglycerides, which are fatty acids that are responsible for the coffee’s flavor and aroma. These triglycerides are broken down by the heat of the roaster, and the oils are released.

The oils released during the roasting process also contribute to the unique flavor of the coffee. The oils contain compounds called esters which provide coffee with its characteristic flavor.

These compounds also interact with the proteins and sugars present in the beans and contribute to improving flavor.

It is important to note that the oils released during roasting can be harmful if they are not handled properly. They need to be stored in an airtight container and kept away from heat and light, as these will cause the oils to break down.

If the beans are not stored or handled properly, they can contain rancid oil, leading to off-flavors and a less-than-ideal cup of coffee.

Are Oily Coffee Beans Good or Bad?

Now that we understand the underlying reasons behind shiny coffee beans, the question comes “is this a good thing or bad?”

Oily coffee beans have been a subject of debate among coffee aficionados for some time now.

On one hand, some believe that the residual oil on the beans helps to improve the flavor and texture of the final cup. On the other hand, some say that oil can ruin the flavor and make the coffee taste unpleasant.

The truth is that ideal coffee depends on how you prefer it.

Many people find that the added coffee oil on the over-roasted beans can give a more intense flavor to the final cup of coffee, making it more robust and full-bodied. This is especially true for dark-roasted coffee beans and espresso blends.

Some people don’t like the oily texture of roasted coffee beans and may find that it detracts from the flavor of the coffee.

Another factor to consider is the freshness of the beans. If the beans are fresh, the oil on them will help to lock in the flavor, ensuring that the coffee tastes better for longer.

However, if the beans are old and the oil has had time to oxidize, the flavor of the coffee will be affected.

For some people, oily coffee is difficult to digest. So, you may want to start with a light roast if you’re not accustomed to drinking coffee oils from long roast.

What Are Some Problems with Oily Beans?

Oily coffee beans can sometimes cause weird problems:

Bitter Taste

The first issue with oily coffee beans is that they can produce a bitter taste. This is because the oils can interact with the acids in the beans, creating a bitter flavor.

While some people may prefer the taste of a bitter cup of coffee, it isn’t for everyone.

Also, the bitter taste can be intensified if the beans are over-extracted. Therefore, it’s important to use the right burr grinders and water temperature when brewing coffee.

Clog Filters

Another problem with oily beans is that they can clog filters.

This can be a particular issue with metal filters, as the oils can get stuck in the small holes and block the flow of water. This can result in a weak, watery cup of coffee.

If you’re using a paper filter, the oils may not block the flow of water, but they can still affect the taste of the finished product.

Damaged Equipment

Oily beans can put extra strain on your grinder or espresso machine.

This is because the oils can collect in the brewing chamber and other parts of the espresso machine, making it difficult for the water to pass through.

If this happens, the automatic coffee machines may need to be taken apart and cleaned. This can be a time-consuming process and can also lead to expensive repairs.

When Should You Pay More Attention to Oily Beans?

If you have a fully automated expresso maker!

The machine grinders inside the espresso machine might be fussier. Oily bean tends to adhere to the walls of the grinder which will gradually impair the performance of your machine.

Continued usage of oily beans may result in exorbitant maintenance costs (regular cleaning) and equipment downtime. It may also alter the flavor of your espresso and result in an unpleasant aftertaste.

That’s why we don’t recommend using very dark roasts (more oily) for espresso machines. You can instead use a French press with medium-dark roasts.

How Can I Prevent Oily Coffee Beans Problems?

Here are some tips on how to prevent oily coffee beans:

Choose the light to medium roast coffee – The darker the roast, the more surface oil will be released. Choose a light-roasted coffee or medium-roasted coffee for the best flavor and the least amount of oil.

Buy fresh coffee grounds – Older coffee beans start to lose their flavor and oils as soon as they are roasted. Buy freshly roasted beans or coffee grounds from a reputable source.

Use pre-ground dark roast – Pre-ground dark roast coffee beans can be used as an alternative to freshly roasted coffee beans. Grinding your beans just before brewing will help to keep the oils locked in the beans and not released during the brewing methods.

Clean your coffee maker – Oils can build up in your coffee maker over time. Regularly cleaning your coffee machine with vinegar or a special cleaner will help to remove any built-up oils. Or you can instead use a manual burr grinder.

Store properly – It’s important to store your beans in a cool, dry place to keep the oils from going rancid or becoming low-quality coffee beans. An airtight container is best. You can read this article on storing coffee beans for more advice on this.

Don’t use flavored coffee beans – Flavored coffee beans tend to have added oils and other ingredients that can increase the risk of oily beans. If you want a flavored coffee, it’s best to purchase unflavored beans and add the flavor yourself.

Use the appropriate amount of coffee-Using too much coffee will result in more oils being extracted, so measure out the appropriate amount of coffee for your brew.

Experiment with different brewing methods– Some brewing methods, like as French press, extract more oils than others, so experiment with different methods to determine which produce less oily coffee.

Experiment with different coffee blends- Some coffee blends are inherently less oily than others, so experiment with different blends to find one that suits your taste and is less oily.

You may limit your consumption of oily coffee beans and enjoy a less greasy, more flavorful cup of coffee by following these steps.

FAQs

Learn how long to store coffee beans and whether they are raw or roasted and the type of storage to ensure they retain maximum freshness and shelf life.

Coffee is one of the most beloved beverages in the world. The USA tops the list as the country that drinks the most coffee in the world. 

Did you know that coffee beans are the main ingredient in coffee? They are the seeds or berries that are used to make coffee. 

Coffee lovers prefer to grind coffee beans to make their coffee freshly. But coffee beans are expensive and difficult to store. They may lose their flavor and aroma if not kept properly after a few days.

In this article, we will provide you with an introduction to how long coffee beans last.

Factors That Affect The Shelf Life Of Coffee Beans

You’ve spent a good amount of money on buying the best coffee beans. 

But if you are not careful about how you store them, you’ll be disappointed with the results. 

So, let’s run through the factors that affect the shelf life of coffee beans. 

According to the National Coffee Association, the main factors that affect the quality and taste of coffee beans are:

1. Heat

Coffee beans are best stored at room temperature or even in a cooler place like in a kitchen cabinet. 

Put them too close to the stove or oven, the heat will affect the beans and cause them to lose their flavor and aroma.

2. Air

When air seeps through the packaging, oxidation occurs where oxygen reacts with the coffee beans and makes them lose their fresh aroma and taste.

That’s why invest in airtight packaging like opaque containers or resealable bags with air valves. 

These bags help keep oxygen from entering and reacting with the coffee beans while making a vent for the carbon dioxide to escape from the beans. 

3. Moisture

Water content from the air or humidity can cause coffee beans to become stale and moldy. 

Once moisture comes in contact with coffee beans, the flavor will lose its original intensity. 

You should not only use airtight containers to store coffee beans but also keep the container in a dry place, away from any source of moisture. 

4. Light

Direct light also affects the quality and shelf life of coffee beans by triggering photodegradation whereby molecules are broken down and the taste and aroma of the coffee beans change.

When light contacts the coffee beans, the oxidation process takes place faster and disintegrates the aroma oils from the coffee beans, resulting in a loss of flavor. 

What’s The Shelf Life Of Whole Roasted Coffee Beans?

Roasted coffee beans last a long time. Because the whole roasted coffee beans are dry, there is very little chance of mold growth, unless you keep the beans in a moist place.

Freshly roasted coffee beans remain fresh for two to three weeks. 

If you store them in an airtight, opaque container with a one-way valve, you can extend their freshness window to one month.

That said, roasted coffee beans won’t last forever even if you store them in airtight canisters and keep them in a dark and dry space. Beyond a specific time, they will lose their flavor and aroma. 

Light vs Dark Roasted Coffee Beans

The freshest state of whole roasted coffee beans varies from bean to bean. Compared to light-roasted coffee beans, dark-roasted coffee beans stale faster. 

That’s because dark roasted beans have been roasted for a longer time, cracking them open, making them more porous, and releasing more oils to the surface that react with the oxygen in the air faster. This makes them lose their fresh aroma and taste sooner. 

Lightly roasted coffee beans last up to six weeks after the roasting date. Due to a shorter roasting time, lightly roasted coffee beans have a longer shelf life since the coffee pods are not cracked and can seal in all the aroma and flavor. 

Different Coffee Storage Methods (Impact on Coffee Flavor)

✍️ Note: It’s best to store coffee in a cool, dark place and to consume it within 2-3 weeks of roasting for the best flavor.

The storage method has a lot to do with retaining the freshness of roasted whole coffee beans. 

Within 12 months after the roast date, whole coffee beans will still be fresh if stored in a one-way valve nitrogen-flushed bag or a simple pouch with a valve.

Nitrogen flushing is a process by which oxygen is replaced by nitrogen from food product packaging. Since nitrogen doesn’t react with food or change its texture, flavor, or taste, they stay fresher for a longer period. 

Moreover, nitrogen is a denser gas than oxygen and surrounds the food products and protects them in transit or on the shelf. 

On the other hand, vacuum sealing simply removes the air from the packaging before it’s sealed. Nitrogen or any other gas is absent from such sealing. 

The shelf life of roasted whole beans can be extended to three to five months when they are vacuum-sealed. You can do this at home with the help of a vacuum sealer.

If properly frozen, roasted coffee can have up to three years of shelf life.

However, these should be used within a week after taking them out of the freezer.

How Long To Store Green Coffee Beans?

Green coffee beans are unroasted coffee beans that come in hessian sacks to the coffee roasters. 

These unroasted coffee beans stay fresher for a longer time than roasted or ground coffee. This is why many prefer to buy green coffee beans and roast them at home. 

These raw coffee beans can last for up to a few years if stored inside a vacuum-sealed bag and at room temperature. 

Always store coffee in an airtight, opaque container in a place away from heat, light, air, and moisture, preferably in a kitchen cabinet. 

When green coffee beans are exposed to the elements, they lose their flavor. 

Stored properly, green coffee beans last up to two years after being opened and stored in a cotton/burlap bag in a cool, dry place. Avoid placing the beans in direct sunlight. 

If green coffee beans are frozen in vacuum-sealed bags, they will last for eternity. That’s because the beans are protected from oxidation or exposure to light or other odors – the ideal condition to keep your raw coffee beans fresh for years.

But it’s difficult to keep your freezer space occupied for so long. 

Moreover, if you keep all the green coffee beans in the same bag in the freezer, thawing them and then refreezing them will take a toll on the aroma and taste. 

Instead, divide smaller portions of the coffee per week and put them away in small freezer bags. This way, you will use them up at the right them without having to worry about the freshness of the beans. 

24 hours before you roast the raw coffee beans, take out one bag from the freezer and roast them for the whole week. 

Pro Tip: If you’re planning to buy green coffee beans for home, don’t buy more than a year’s worth of them to retain maximum freshness. 

How To Keep Ground Coffee Fresh

There are many people like me who don’t have a coffee burr at home and prefer to buy fresh ground coffee. 

Ground roasted coffee lasts approximately 2 to 4 months if stored in an unopened bag.

It can lose its flavor within 15 minutes when exposed to air as ground coffee has a larger surface area through which it loses its oils and aroma. 

If maintained in its original packaging after opening, ground coffee should ideally be consumed within a week.

By keeping ground coffee in an airtight container, you may extend its freshness.

You may also like: Do Coffee Grounds Go Bad? Find Out the Truth!

How Does Coffee Degassing Affect Shelf Life?

Did you know that during and right after the process of roasting coffee beans a chemical reaction takes place that releases carbon dioxide from the freshly roasted beans?

Degassing is the process where all the carbon dioxide from the roasted beans is released over a period of time. 

This not only has an impact on the taste of the brew but also on the shelf life of the coffee beans.

Coffee beans emit gases more quickly in the early days after roasting.

The newly roasted grounds release CO2 gas throughout the brewing process, creating bubbles.

These bubbles may interfere with the water’s ability to contact the ground beans, which could result in uneven extraction.

That’s why it’s advised to wait for a few days for the coffee to degas after roasting before you proceed to grinding it and making a cup of coffee. 

This time frame could range from one to five days, depending on the brewing method.

For instance, if you use a French press to brew your coffee, your coffee beans are ready for use one to two days after roasting.

Wait for five to seven days following the roasting date before using the beans for espresso.

And if you are into pour-over coffee, bubbles from the freshly roasted coffee are a sign of freshness and should be appreciated.

😀 Fun Fact: Coffee beans tend to lose their flavor slower after roasting and during degassing.

So, if you want to know if the pack of roasted coffee beans you just got is fresh enough, simply put them in a plastic Ziploc bag and press out as much air as possible. 

Seal the bag and leave it overnight. 

If you find out in the morning that the plastic bag has filled out with air, that means the coffee beans are freshly roasted and still degassing. 

With your mind at ease, it’s best to store your roasted coffee beans in a coffee bean container with a CO2 valve. 

Tips To Store Coffee Beans

If you want to find out how long to keep coffee beans after opening, follow the tips below.

1. Buy fresh coffee beans from a nearby roaster that roasts in small batches. 
2. Buy roasted whole coffee beans instead of ground coffee. 
3. Grind coffee beans at home using a coffee grinder. This way, the coffee beans stay fresh for longer.
4. Grind coffee only when you need them as storing ground coffee will cause it to go stale.
5. The simplest solution is just to keep them in there if your coffee is packaged in an opaque resealable bag. Otherwise, use an opaque, airtight container to store the coffee beans to prevent exposure to light. 
6. Avoid bulk buying coffee beans as the quality decreases over time.
7. Avoid refrigerating coffee beans as this will affect their smell and taste. 
8. Put coffee beans in double bags and store them in the freezer if you’re not going to use them anytime soon. This will prevent moisture from coming in contact with the coffee beans.

How To Detect Stale Coffee Beans

These are the top telltale signs that your coffee beans have gone stale.

1. Residue

Take some coffee beans in your hands. If you see residue on your hands, that’s a sure sign they have become stale. 

2. Smell

If the coffee beans don’t give off their usual aroma, they are not fresh anymore. 

3. Taste

A cup of coffee that leaves a bitter aftertaste and smells nothing of the caramel, toffee, or nutty flavors that you were expecting is most likely stale. 

4. Looks

By just looking at the coffee beans, you can tell if they’re fresh or not. 

Fresh coffee beans release oil that gives them a sheen. 

If the sheen is missing, the coffee beans are not fresh anymore.

Moreover, if you notice mold on coffee beans, you need to throw them out. 

5. Packaging

Coffee beans need to release gas after they have been roasted. So, look for air valves or holes in the packaging. 

If there are none, the coffee beans inside have indeed gone stale.

The Bottom Line

The key to keeping coffee beans fresh is to store them well. 

Even beyond the expiration date on the bag, you can safely use coffee beans if you have stored them in an airtight container. 

Remember that any contact with light, air, heat, and moisture will cause coffee beans to lose their fresh taste and even become moldy. 

Or, if you bought coffee beans in bulk, freeze them in freezer bags and they’ll be fine. 

FAQs