The secret ingredient to a better pot of coffee: a clean coffee maker!

When was the last time you properly cleaned your coffee maker? Not just a wipe or rinse of the pot itself, but a full-on cleaning of the actual machine? According to Consumer Reports, your coffee maker should be given a good cleaning every three to six months, but it’s not uncommon for people to let it go much, much longer—especially in an office setting. After all, if the coffee maker or espresso machine itself doesn’t look dirty, you’ll probably clean elsewhere.

Wondering how bad it can be to skip this chore? Sip on this. In 2011, the National Sanitation Foundation found that 50% of the coffee machine water reservoirs they tested had grown yeast and mold. If left to fester, these growths can even have a negative impact on coffee drinkers’ health, particularly when it comes to individuals with allergies. Bacteria (coliform) was also found on some of the reservoirs tested. For comparison, the tainted coffee makers weren’t as dirty as the pet bowls the NSF tested (Ew!), but they were germier than the average bathroom faucet handle. Now, do you still want to use that unclean machine to make your coffee every morning?

Mineral deposits are also an issue in under-serviced coffee machines. Without regular cleaning, your machine’s carafe, tubes, and burner can get clogged over time with built-up minerals, impacting both the quality of your coffee and the function of your machine. Coffee machines in kitchens with hard water are more likely to run into build-up, but any type of water can eventually cause this issue. This is where descaling (which is different than simply cleaning) is important, since that stubborn buildup can often make your coffee bitter, weak, or just plain bad.

In addition to all those external factors, there’s also the impact  itself has on your machine. If your coffee is becoming increasingly bitter, it could be due to the grounds’ natural oils building up in your machine; these oils can’t be removed with water, and if more and more oils remain on your brewing basket or in other parts of your coffee maker, your coffee’s flavor could go straight downhill.

None of this is necessarily dangerous, especially for those of us with healthy immune systems, but we can probably all agree that it’s not ideal.

Convinced that it’s time to clean that coffee maker? Here’s what you need to know to get started.

Cleaning your coffee machine daily

Before you get started, make sure you understand what the different parts of your coffee maker are, how to clean each of them, what to use, and how often they need to be cleaned.

Naturally, this will vary a bit, depending on your coffee machine. Cleaning a Keurig, for example, will look a little different than cleaning a standard drip coffee maker. But between these tips, and a glance at your machine’s manual, you should be ready to roll in no time.

As far as cleaning supplies go, water and dish soap (especially one designed to cut through oil) will get you started. A clean sponge will also come in handy, but keep in mind that a sponge that’s been used over and over may just make your coffee pot dirtier, so a clean cloth may be a better choice.

Here are some tips to keep in mind when brewing coffee daily:

• Right after your coffee finishes brewing: Toss (or compost) your grounds, along with the machine’s paper filter, if you use one. Leaving wet grounds in the coffee maker leads to increased growth of mold, yeast, and bacteria. Use a clean, damp towel to clean up any coffee residue remaining in the brew basket and wipe down the outside of the machine if you find coffee residue there, too.

The water reservoir (which may be referred to as a chamber) also requires daily attention, so wipe that dry as best you can. Then, let the machine thoroughly air dry with the latch open.

• Before the day is done: Anything detachable should be hand-washed with hot water, dish soap (ideally a brand designed to remove oil), and a clean, non-abrasive sponge to loosen those coffee oils and residue, along with pesky germs. Don’t forget all the nooks and crannies, and pay close attention to high-touch surfaces, like the coffee pot handle, since those are natural spots for there to be loads of germs.Afterwards, wipe the machine dry and allow it to air out until morning. A dishwasher might also be an option for any detachable components labeled as “dishwasher safe” (like brewing baskets and non-thermal glass carafes). Check for that information on either the component itself or in your machine’s manual. If possible, keep the coffee maker disassembled until all parts are completely dry.
• For stubborn stains: If you find burnt-on coffee stains on the hot plate or drip tray, allow the machine to cool completely, then scrub with a damp sponge and a little baking soda. Glass carafes can also begin to look dark and dingy after heavy use; if that’s the case with yours, fill the carafe with a solution of two parts hot water and one part baking soda. Leave it overnight to let it soak, and then, in the morning, rinse it thoroughly before making your next batch of coffee. No baking soda? No problem. Swirl a little uncooked rice with warm, sudsy water in the carafe and watch the gunk loosen right up.
• Other considerations: Since you’re in the habit of properly washing your coffee machine now, make sure your coffee cup or travel mug gets the same treatment.

Cleaning your coffee machine every month (or so)

Although a daily cleaning will keep the outside of your machine and certain components germ-free, the inside of your machine is a different matter. That’s where that pesky mineral build-up can occur, so it’s important to set time aside on a regular basis to do a cleaning cycle designed to deal with that issue. This is sometimes referred to as descaling or decalcifying, but regardless of the word choice, the issue—and the process for taking care of it—remains the same. Most manufacturers and experts recommend doing this monthly, although some manufacturer’s recommendations extend that timeframe to every six months.

Your coffee maker’s manual might have specific instructions, possibly directing you to run a brew cycle using a descaling solution. Some coffee makers even have a dedicated cleaning cycle, so it’s certainly worth doing a little research to make sure you’re taking the preferred approach.

However, if your machine doesn’t direct you toward a specific process or cycle, using a mixture of vinegar and water on a monthly basis is a popular and effective solution.

Be aware, though, that if your machine’s manual specifies that you use a certain descaling solution, there could be parts of your machine that can be damaged by vinegar. So, if instructions are provided, it’s wise to follow them (or at least do a little more research on your machine’s needs).

Assuming your coffee maker is good to go with a vinegar solution, here’s how to do it:

• Fill your reservoir with a mixture of half white vinegar and half water; if you normally use a paper filter, add one, but skip the coffee grounds.
• Run half a drip cycle, then let it sit for 30 to 60 minutes to allow the vinegar solution to fully penetrate the tank and tubes.
  • Unless your machine has a cleaning cycle or self-cleaning mode, this will likely mean manually stopping the cycle at the midpoint, so don’t wander off!
• Then, let the cycle continue to completion, dump the brewed water (and paper filter, if you used one), and run another couple of brew cycles with plain water (using new paper filters each time) to ensure the vinegar taste is fully removed.

Cleaning your coffee maker when you’re in a rush

Some mornings, just finding time to make coffee is a challenge, let alone doing a thorough cleaning of the full machine. While it’s ideal to follow the daily (and monthly) steps outlined above, life happens, and it’s helpful to keep in mind that skipping a cleaning now and again isn’t all that harmful. When you’re short on time, shorten your to-do list to just the following:

• Dump coffee grounds and filter.
• Empty reservoir and leave it open to dry.
• Empty and rinse your coffee pot.

The next day, you can get back to a full cleaning with warm, soapy water, but this will at least slow the growth of any nasties you’re trying to avoid—and a missed day, now and again, is unlikely to have any major impact on the flavor of your coffee.

Conclusion

Overall, any effort you make toward keeping your coffee maker clean is going to be better than nothing, so stick with it and don’t be too much of a perfectionist. Just do your best, try to make cleaning a daily habit, and set yourself reminders to descale your machine regularly. With these tips, your coffee maker will be happier and healthier—and you’ll enjoy a tastier brew, too.