You pop a k-cup into a machine, hit a button, and have a hot cup of coffee in a snap. This is what the average morning looks like for many American coffee drinkers. Roughly one in four had a single-serve coffee machine like the ever-popular Keurig as of 2020.
The convenience of a Keurig is undeniably great on a busy morning. Unfortunately, this particular modern convenience doesn’t come without risks. If you’ve been getting sick without a known cause, you may want to make sure you’re not experiencing symptoms of Keurig sickness.
The scary fact is that up to half of household coffee machines are contaminated with yeast and mold. Yet, moldy coffee maker symptoms are easily overlooked or blamed on something else entirely. Is it possible you’ve been drinking moldy coffee and unwittingly overlooking the ill effects? Take a closer look at the symptoms of Keurig sickness and more below.
By the way: this article is mainly focused on the potential acute health affects of a moldy Keurig machine. For more information on the more longterm risks of plastic coffee pods from estrogenic activity, click here.
Table of Contents
- What Happens If You Drink Moldy Coffee?
- Symptoms of Keurig Sickness
- How Does a Moldy Coffee Maker Happen?
- How Do You Know If Your Coffee Maker Is Moldy?
- How to Clean a Moldy Coffee Maker
- How to Prevent a Moldy Coffee Maker
- Other Coffee and Mold FAQs
- Can mold grow on coffee beans?
- Will using vinegar to clean your coffee maker give you better-tasting coffee?
- If you clean your Keurig machine and the coffee still tastes off, what should you do?
- Can you get food poisoning from a dirty Keurig machine?
- How do I get the mildew smell out of my coffee maker?
- Coffee Makers and Mold: Takeaways to Remember
What Happens If You Drink Moldy Coffee?
Drinking moldy coffee just one time is not likely to send you to the emergency room or spiraling into a serious illness. (Of course, some individuals are more sensitive than others, and those diagnosed with CIRS or experienced mold-related illness in the past should be extra careful here.)
Nevertheless, consistent exposure to mold from a coffee maker can definitely lead to illness for anyone.
When you consume mold, toxic chemicals known as mycotoxins can accumulate in your system. Certain mycotoxins from mold are capable of causing illness or even death, but the severity of the situation depends on several factors, such as:
- The age of the individual exposed
- The immune system health of the individual exposed
- How much mold is consumed
- How long you are exposed to mold-related mycotoxins
- Genetic susceptibility
- History of mold-related illness
Something to keep in mind that may soothe the alarm of being exposed to mold growth in your coffee is the fact that most people are exposed to some mycotoxins with their regular diets. Some sources claim that roughly one-quarter of grain-based products have some level of mycotoxin contamination due to mold. Many other foods may contain some level of mold as well. However, there are safety limits in place that food producers must follow to keep exposure at a minimum.
As mentioned before, some people are especially sensitive to mold-related mycotoxins. However, moldy coffee maker symptoms are possible for anyone. Mold in your coffee may become problematic if you are consuming a lot of mold on occasion or even if you are consuming a little mold on a daily basis.
Symptoms of Keurig Sickness
Symptoms of Keurig sickness can range from mild to severe, and symptoms will likely be more intense if you have a mold allergy or CIRS diagnosis. For instance, if you suffer from a mold allergy, you could experience allergic reactions like a runny nose, itchy eyes and throat, and even wheezing or sneezing.
Different types of mold can generate different sets of symptoms. And different types of mold may be growing in your coffee maker. One study in 2017 actually discovered six different types of mold inside one Keurig coffee machine. Therefore, excessive mold exposure due to drinking coffee with mold may not always look the same for each individual. General symptoms of mold ingestion can include:
- Skin rash
- Irritated eyes
- Stomach cramps
Even people who do not have a mold allergy or sensitivity can experience respiratory symptoms with mold exposure. However, individuals with asthma or a compromised immune system are more likely to have symptoms related to the respiratory tract with mold exposure.
How Does a Moldy Coffee Maker Happen?
Mold spores are simple microscopic fungi necessary to the environment. Their role is to break down organic materials. Therefore, mold spores—which are a bit like airborne seeds—are almost always hanging around. When a moist environment is found, mold spores plant themselves in the area and begin to multiply, and this process happens quickly.
Mold colonies can start to develop on a moist surface within a mere 24 to 48 hours. Even allowing a machine to sit idle over the course of a few days could allow mold growth to begin.
Mold needs two things in its environment to thrive: moisture and lack of sunlight. Sadly, the average single-cup coffee brewer provides the perfect environment within its water reservoir to grow mold because there is no penetrating sunlight and ample amounts of moisture. Pair this with the fact that most people don’t flush their Keurigs or coffee makers on a regular basis, and you’ve got a moldy disaster waiting to happen.
It should be noted: single-cup coffee machines are not the only culprits for coffee mold spores. These spores can collect in a drip-style coffee machine’s filter basket, left-behind wet coffee grounds, drip trays, and/or water tank.
How Do You Know If Your Coffee Maker Is Moldy?
Unfortunately, most people don’t see coffee maker mold or catch a moldy coffee machine before they actually use it. One reason Keurig coffee makers get such a bad rap is that the machine’s water reservoir and the water lines that lead from the water tank to the coffee pod compartment are not easily viewable. Therefore, visible mold may be undetectable by the human eye because you simply can’t see all the small cracks and crevices.
The best telltale indicator that you have a moldy coffee machine is if your coffee tastes off. You may feel like your brew is more bitter than it should be or has a somewhat musky taste. Most coffee lovers can quickly point out when their favorite cuppa joe tastes weird. But, most coffee lovers will also assume there is something wrong with their coffee or coffee beans and not the coffee maker itself.
In the event you’ve allowed your coffee maker to sit unused and uncleaned, it is likely best to assume there is mold already growing somewhere. Therefore, learning how to clean a moldy coffee maker—even if you’re not certain that mold is the problem—is for the best.
How to Clean a Moldy Coffee Maker
Whether you suspect you’ve been dealing with moldy coffee maker symptoms or not, thoroughly cleaning your coffee maker periodically is recommended. Keeping your coffee maker clean should involve both daily efforts and periodic deep-cleaning processes to eradicate any potential mold and bacteria. Contrary to what a lot of people assume, simply running hot water through a coffee maker or the heat generated during the coffee brewing process is not enough to prevent coffee maker mold.
Each type of coffee maker can have its own manufacturer-recommended cleaning tips. For most single-cup coffee makers, the general recommendations for cleaning the machine are similar:
- Take all removable components off the machine and clean them with soapy water (dish soap is fine)
- Use a small brush or toothpick to remove any spots of debris in small crevices you can see
- Fill the water reservoir with one part plain water and one part white vinegar until it is full
- Allow the mixture to sit in the reservoir for a short period
- Run the solution through the machine with a brew cycle
- Run another cycle of fresh water through the machine
Kuerig actually recommends all machines be deep-cleaned with a descaling solution periodically to remove any mineral buildup that can come along with using tap water in the machine. This solution may not eradicate mold, but it will help keep calcium deposits at bay that can harbor mold and bacteria.
With a standard drip coffee maker, you can also use a vinegar/water solution to clean out the reservoir and parts. Simply run a coffee pot full of vinegar and water through the machine with only a clean paper filter in the brew basket and follow with another brewing cycle with plain water.
If your coffee maker is very moldy and you are sensitive to mold, you may want to consider replacing the coffee maker entirely, as you may not be able to fully eliminate all of the mold that’s grown. You may also want to consider using a coffee maker with fewer small parts where mold can grow, such as a pour over or French press.
How to Prevent a Moldy Coffee Maker
With a moldy coffee maker, the old adage that an ounce of prevention is worth a pound of cure definitely applies. In other words, the safest way to avoid getting sick due to moldy coffee is to prevent mold from occurring.
Standard Coffee Makers
A few simple steps can help you prevent mold and bacteria from getting trapped in your standard drip coffee machine, such as:
- Clean your coffee maker’s carafe and basket after each use and allow it to air dry
- Detach other removable parts periodically and wash them with soap and water (i.e. drip trays or water tanks)
- Make sure non-detachable water reservoirs are empty and clean. Leave the lid open to allow air-drying
- Never leave a filter basket or filter with coffee grounds in place for more than a few hours
- Run a white vinegar/water mixture through the coffee maker every few months
Single-Cup Coffee Makers
Keurigs and similar coffee machines can be a little more difficult to keep clean and prevent mold growth, but not impossible. A few pointers to prevent mold with a single-cup coffee maker include:
- Never go more than a few days without changing unused water in the water tank
- Empty the water reservoir fully if you won’t be using the machine for a couple of days. Dry it completely and leave the lid open.
- Clean the detachable parts like the filter holder, K-cup holder, and drip tray weekly
- Replace the charcoal filter (if equipped) with a new filter every other month or every 60 water refills
- Clean reusable k-cups with soapy water after each use and allow them to dry completely
Other Coffee and Mold FAQs
Can mold grow on coffee beans?
Yes, mold can develop on coffee beans and ground coffee if the coffee is not stored properly. Be sure to always store opened packages of coffee in an airtight container and discard any coffee that has been exposed to moisture.
Will using vinegar to clean your coffee maker give you better-tasting coffee?
It is very possible that you will experience a better taste when brewing coffee for the first time after you do a deep clean with vinegar. Not only will this flush out mold, but bacteria and accumulated minerals will be washed away as well. Therefore, your coffee can heave a cleaner, less bitter taste from a clean coffee maker.
If you clean your Keurig machine and the coffee still tastes off, what should you do?
If you’ve followed all the recommendations to deep clean your Keurig, make sure you have changed the filter. If your filter is good, and you still experience bad-tasting coffee, it may be time to consider replacing your machine. Machines that have a great deal of scaly buildup or internal residue can be beyond saving.
Can you get food poisoning from a dirty Keurig machine?
It is very possible to get some type of food poisoning from a contaminated machine. Food poisoning can stem from exposure to bacteria like E. coli and salmonella, which could make their way into your coffee if you do not clean your coffee maker or coffee pot thoroughly.
How do I get the mildew smell out of my coffee maker?
Flushing your coffee maker by doing a brew cycle of half vinegar and half water should eradicate any mildewy odors. Remember, an odor of mildew is a sign that mold could still be present. Therefore, if you have followed the recommended cleaning routine and deep clean methods and still experience an odor, the coffee equipment may need to be replaced.
Coffee Makers and Mold: Takeaways to Remember
Whether you use a Keurig for your morning java or a standard coffee maker, mold growth is a possibility. Moldy coffee can be a health risk, especially with everyday exposure or if you are sensitive to mold.
There are steps you can take to prevent mold from growing, including both basic cleaning daily and periodic deep cleans to flush away any hazardous contaminants. Lastly, when in doubt about your coffee maker due to odd odors and bad-tasting coffee, it may be best to consider replacing your equipment to protect your health.