Coffee being poured into a cup by the machine -

Do Keurigs Get Moldy? (The Best Way to Clean Your Coffee Maker)

A dirty coffee brewer can make awful tasting coffee—or worse, mold! You don’t want to drink that in the morning.

So, let’s get started!

Do Keurig machines grow mold?

Yes. Keurigs (as well as most other coffee makers) can contain bacteria and become moldy. This can end up in the coffee, making people very sick. Like most coffee makers, Keurigs need to be properly cleaned on a regular basis (usually every 2–4 months). But it can be hard because a brewer has so many parts, but it’s important to do so so that things like this don’t happen.

What causes mold to grow in a coffee maker?

The most common source of brewer mold is the combination of water and leftover coffee. According to the Center for Disease Control and Prevention (CDC), mold grows where there is moisture.

It can travel into your home through open doors, windows, vents, and your cooling and heating system. Mold can even be brought in physically through our clothes, shoes, and even our pets.

There’s just no possible way to prevent mold from entering our coffee maker because during its initial stage, it’s just not visible to the eyes.

We are only made aware of its presence after it has taken its place and grown into a sizable amount.

Unfortunately for us, a Keurig machine is often forgotten because of the perception that it’s somewhat automated. As a result of this misconception, it doesn’t need much maintenance.

What are the risks of having a moldy Keurig?

  • May contain harmful toxins and spores
  • May cause stomach pain, nausea, and other symptoms in some people
  • May cause illness in people with sensitive immune systems
  • May cause allergic reactions in some people
  • May affect the quality of the coffee brewed by the machine
  • Can clog up parts of the machine and reduce its efficiency
  • May cause damage to the exterior of the machine
  • May cause the machine to fail prematurely

Is it safe to use my Keurig if it has mold?

No, it is not safe to use a Keurig that has mold. Mold can cause a variety of health problems, including allergic reactions and respiratory issues, and can also affect the taste of your coffee or tea.

It is important to thoroughly clean your Keurig if you suspect mold growth and not use it until it has been properly cleaned and sanitized.

Using the steps here to clean your Keurig will help get rid of any mold and make sure it is safe to use.

What would happen if you drank moldy coffee?

The real question is, should you be worried if you ate or drank moldy food?

According to Healthline, probably not. Mold might produce harmful mycotoxins that can end up in your coffee. Exposure to small amounts likely won’t cause any harm to people who are healthy and have a strong immune system.

Mycotoxins are known to cause a lot of adverse effects in humans when they are inhaled or consumed. In fact, a mycotoxin called Aflatoxin B1 that can be found in old and rotting coffee beans is strongly linked to the risk of liver cancer.

However, speculation says that you most likely won’t continually eat that moldy food or drink after its molding growth process is too far advanced.

In other words, your coffee will probably end up tasting way too bad and you should naturally have stopped drinking at some point before it ever becomes a real issue.

However, it is important to avoid ingesting it when you can. With mycotoxins, depending on the amount you ingest and how long you’ve been exposed to them, they can do a great deal of damage to your health.

What to do if I drink mold from a Keurig?

If you have accidentally consumed mold from a Keurig, it is important to monitor your symptoms and seek medical attention if necessary.

As stated by the Functional Medical Institute, some of the signs and symptoms of being overly exposed to mold would be:

  • Brain fog
  • Memory problems
  • Trouble focusing
  • Headaches
  • Fatigue and weakness
  • Muscle cramps
  • Joint pain
  • Nerve pain
  • Numbness and tingling
  • Red and light-sensitive eyes
  • Asthma, cough, and shortness of breath
  • Tremors and vertigo
  • Change in appetite, diarrhea, nausea, and abdominal pain
  • Metallic taste
  • Chills and night sweat
  • Increased thirst and urination

If you experience any of these symptoms after consuming mold, it is recommended to contact a medical professional or seek medical attention immediately.

How do I identify mold in coffee?

Mold in coffee can be identified by its appearance, smell, and taste. Here are some ways to identify mold in your coffee:


  • Mold in coffee can appear as fuzzy or slimy patches on the surface of the coffee.
  • It can also appear as black or white spots on the coffee beans or grounds.


  • Mold in coffee can have a musty or earthy odor.
  • It can also have a sour smell or a smell similar to wet cardboard.


  • Mold in coffee can have a bitter or sour taste.
  • It can also have a metallic taste or a taste similar to dirt.

How often should you clean your Keurig?

The company that creates Keurig recommends a few key occasions of when to clean your Keurig machine.

  • Clean the outside exterior of your Keurig regularly.
  • Cleaning the water reservoir and lid should be done once a week.
  • You will also need to de-scale your machine every 3 to 6 months.
  • Replace the water filter cartridge every 2 months.

Through experience and reviews, I’ve found that there are several other occasions when you can tell your brewer needs cleaning.

Experiencing any of these issues is a sign that you haven’t properly cleaned your brewer on time. And that you should take a more active approach in reminding yourself to clean it.

  • If you start to see mold or smell a foul odor inside the compartments of your machine
  • If the Keurig is exhibiting slower than usual drip
  • If you see calcium or mineral build-up inside the machine
  • If your coffee begins to taste different from before (particularly more bitterness than usual)
  • If you begin experiencing signs and symptoms explained above
  • When you taste a slimy muckiness texture in your coffee
  • If there are black specks coming out into the coffee

How to properly clean a Keurig machine

  1. Start by emptying the water from the reservoir.
  2. Wash all removable parts of the coffee maker in a sink with dish liquid and water.
  3. Get an old toothbrush dipped in vinegar and use it to clean all the hard-to-reach areas inside the machine.
  4. Take out the reusable filters and make sure to rinse and wash those down until they are visibly clean.
  5. If you have a reusable pod, go ahead and wash that as well.
  6. Reassemble your machine with the exception of the filter.
  7. Mix 3 cups of vinegar and 3 cups of water into the reservoir and run it through the brewer until the reservoir is empty. You’ll end up with very dirty vinegar water.
  8. Repeat step 7, but this time with water several times to drive out any remaining vinegar.

Tips to prevent your Keurig machine from getting dirty and building up mold

  • Regularly clean the brewer and its components – I can’t stress how important it is to keep a schedule on cleaning the Keurig. I’ve used my Google Calendar and have set these events to regularly remind myself of the times. Just create one for reservoir cleaning and set it to remind you weekly. Create another one to change the filter every 2 months. Finally, create one to de-scale every 3 to 6 months.
  • De-scale your Keurig every 3 to 6 months – Scale is a mineral deposit build-up that can prevent the machine from brewing and filtering properly. The mineral build-up is non-toxic but it will prevent the proper functioning and flow of water through the channels. This can be solved by running a de-scaling solution which you can find here on Amazon or vinegar through the reservoir and machine.
  • Vinegar helps prevent mold – Surprisingly enough, vinegar is a wonderfully natural cleaning agent. I have an article about using vinegar as a natural, safe, and non-invasive cleaner to clean tabletops here.
  • Change the filter regularly – Changing out the filters is important because filters trap particles and even organic substances and after some time. Clogs and residue build-up can occur, resulting in leaks and mold growth.
  • Don’t leave the same water in for too long – I’ve stated before in the article that mold is greatly attracted by water. If you left the same water in the reservoir for a long period of time, it will give mold enough time to settle and grow. Changing water out with a new batch of water will reset this timetable and prevent mold from growing.
  • Properly store coffee and materials in a clean and dry area – If you generally use a traditional coffee maker or reusable K-cup. Coffee grounds and filters should be properly sealed and if possible sealed airtight which you can find on Amazon here. Leaving any of these ingredients of the coffee machine out may lead to mold and bacteria having access to it. Mold and bacteria can practically grow on anything so it’s a good idea to block off all access points.
  • Maintain the machine in a clean and dry environment – Keeping the machine itself in a cool and dry area is important as well. While it isn’t rational to seal it away from the environment, it is important that you don’t leave it in an area where the air is humid and warm. In fact, any area that is humid risks the chances of mold and bacterial.

Can drinking moldy coffee everyday kill you?

Drinking moldy coffee every day can pose health risks and potentially lead to serious health issues. Mold is a type of fungus that can produce harmful toxins called mycotoxins.

Exposure to mycotoxins can lead to a range of symptoms and health problems, including allergic reactions, respiratory issues, liver damage, and even cancer.

The severity of the health risks depends on the type of mold, the level of exposure, and the individual’s sensitivity to mycotoxins.

While drinking a small amount of moldy coffee once may not cause harm, regular consumption of moldy coffee can increase the risk of exposure to mycotoxins and potentially cause health issues over time.

Do Keurig machines grow mold more than the competitors?

Keurig machines do not necessarily grow more mold than their competitors. Mold growth in coffee makers can occur in any type of machine that is not cleaned properly or stored in a damp environment.

But some things may make Keurig machines more likely to get mold than a regular coffee maker with a carafe.

Keurig machines have a complex internal structure with many small parts, which can make it challenging to thoroughly clean and dry all components.

Also, Keurig machines often have a water reservoir that stays wet for a long time. This can create a damp place where mold can grow if it isn’t cleaned regularly.

This can lead to a buildup of mold over time if the machine is not cleaned properly and regularly.

Interesting further reading: