What Causes Oily Film On
Top Of Coffee?

It's morning, and it's time to brew yourself a cup of fresh, delectable coffee. When you lift it to your lips, you see it is dripping with oil. Is this a sign that your coffee beans have spoiled?

The good news is that an oil film on the surface of your coffee is quite natural. We'll discuss why oil accumulates on the rim of your morning coffee cup and what, if anything, you should do about it in this post.

  • Where Is the Oil Really Sourced?

Nope, your coffee machine is not filthy and does not require disposal. However, no one wants to drink coffee that is greasy. Are you curious about the origins of the oil?

Natural oils are a component of coffee beans. 71% of these oils are fatty acids, the same type of fatty acids found in margarine, certain types of meat, and other legumes.

If you grind and brew your own coffee, you may notice a tiny variation in the quality of your beans.

On the surface, some coffee beans appear dry, while others appear oily/shiny.

Coffee beans that are light or medium roast have less oil on the surface. On the other hand, dark roasted coffee beans have a substantial amount of oil on the surface.

Having oil in your coffee doesn't automatically signify that it's gone bad, contrary to what many coffee consumers and enthusiasts believe. Having oil on the surface of your cup or on the beans does not signify that the coffee beans used to brew are low grade.

It's not a bad thing that the coffee has a little oil in it. Most coffee makers and producers agree on one thing: oily coffee or beans are ideal. There are still a few people who are skeptical about these statements, though. Everyone knows that greasy coffee is bad for you, and they make it clear immediately.

Both sides' assertions have some merit, as may be seen through investigation. When it comes to coffee, oil has a split-second impact on whether it's good or poor. How much coffee oil is good for you depends on a number of variables.

If you choose light or medium roast coffee beans, you should always be on the lookout for oil sludge in your cup of joe. This indicates that your coffee beans have gone bad or have been stored incorrectly for a long period of time. Incorrect storage conditions, a lack of humidity and temperature may have led to your coffee beans becoming bad, or you may have used the wrong container or water got on them.

It's also possible to tell if your coffee is fresh and healthy by looking at the amount of oil it has in its beans.

In addition to the suggestions listed above, there are a number of other variables that might affect whether or not your coffee is greasy. Among them are:

  • Water Quality

For the most part, there are soft and hard water. If you're used to drinking oily coffee because you're used to drinking tap water that's either hard or sold packaged as such, you're in for a treat. This is assuming that you brew your coffee using tap water.

Calcium levels are higher in hard water. Ground coffee has a lot of fatty acids, and calcium readily binds to them, making it more noticeable. As a result, there is no fatty acid bonding and no oily residue in soft water.

  • Bean Sorting in the Coffee Industry

Different coffee bean varieties, freshness, and processing methods yield different quality grades of coffee beans. High-quality coffee has a more delicate flavor and is less acidic than its lower-quality counterparts. Because of the lengthy yet gentle process they've undergone, it's less probable that they'll yield greasy coffee.

The acidity of lower-grade coffee beans makes a big impact in the final flavor. Because this coffee is more acidic and has been through a more rigorous production process, it is likely to have a higher percentage of oil residue.

  • Filters for drinking water

If you don't want to see oil in your coffee, water filters can help get rid of some of it, but not all of it. The majority of water filters have an activated carbon coating that can absorb organic residue during the filtration process. Connect your filter to your faucet to collect water with the fewest impurities.

Coffee made with carbon water filters has a significantly lower oil content. However, if you add water softener, you can finally say goodbye to oily coffee. This is due to the fact that soft water has a lower chance of reacting with the compounds found in coffee beans. To maintain effective results, replace the water filters every six months.

One method for avoiding oily coffee is to use water filters. But what about the filters that come with your coffee maker? When brewing coffee, most people use two filters instead of the standard single filter to effectively filter oil from the coffee. While some oil may still seep through, it will be much less noticeable on your coffee / coffee cup.

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About US | OCM Profile

OCM (OnCoffeeMakers.com) was started in 2007 with the first webpage about coffee machines. And for a number of years, we focused on helping people find their desired coffee machine (we still are helping folks with that! So, if you are looking for coffee machines for office or restaurants - check out the link). 

In 2010, we started getting enquiries on restaurant marketing and we start to help food and beverage brands with their marketing. Below are campaigns and events that we have done over the years: 

OCM's campaigns: F&B Marketing Ideas by OCM 

OCM's Events: F&B Industry events by or with OCM

Check out this restaurant marketing guide to learn more about the many campaigns and companies we have worked with. 

Since then, we have also created many marketing workshops and classes for the F&B industry. Many of these modules are still running in tertiary institutions such as Temasek Polytechnic Skillsfuture Academy and also ITE College East COC classes, below are some snippets of our lectures and workshops: 

OCM’s F&B workshops: Food and Beverage Marketing Lectures | Workshops - click to watch classes on customer journey map, JTBD and more. 

So, if you are looking for industry practitioners to help you scale your coffee or F&B businesses, do drop us a message or book an appointment. Do also check out our various social media platforms on regular F&B and coffee market updates: 

For regular coffee (F&B) related videos: OCM Youtube

For Daily Coffee Inspiration (fun coffee content): OCM IG

For insights into the coffee (F&B) industry: OCM LinkedIN 

PS: For the coffee lovers, we continue to share coffee articles (and videos) and have also started a free coffee class section (with free online coffee training supported by coffee partners).

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