There’s a running joke in my family centered around my older sister’s absolute refusal to use a mug or mug with ingrained coffee stains. Although a cup has clearly been washed thoroughly, he refuses to drink any liquid, even coffee, from it.
This provides fodder for funny jabs and inside jokes, but it made me wonder: Why do coffee and tea stain all my cups, and why are the stains so hard to get rid of?
With these questions in mind, I delved into the wide world of coffee stains. I set out to find a solution to prevent stain buildup on mugs, mugs, thermos and coffee pot and I can confidently say that I can now make my sister drink from any cup. Below you’ll discover why coffee (and tea) stains are so stubborn and five effective ways to fight them.
Read more: Learn how to remove stains from clothes, how to clean workout clothes AND how to clean running shoes.
Why does coffee stain cups and mugs?
It’s so frustrating to run cups and mugs through dishwater only to find they’re still stained at the end of the cycle. Before you throw away that old cup, consider it a learning opportunity to research why coffee has such a powerful coloring power.
Coffee can stain cups and mugs due to the presence of compounds called tannins, a type of polyphenol naturally present in coffee beans. During coffee brewing, tannins can adhere to the surface of cups or mugs, causing brown stains over time.
How to avoid coffee stains on cups
The best offense is a good defense. To stop stains before they form, it’s best to rinse a cup or mug immediately after use to prevent stains from forming.
Additionally, coffee stains can be aggravated by other factors, such as the temperature of the coffee, as heat speeds up chemical reactions. The tannic compounds present in hot coffee will adhere more strongly to the cup material. Leaving coffee in the cup or mug for an extended period also makes stains more difficult to remove as tannins settle on the surface of the cup as the coffee cools.
The porosity of the cup material can also affect the likelihood of staining. The more porous the material, the more susceptible it is to liquid absorption and staining. Plastic, terracotta and stone cups or mugs are generally considered more porous. I recommend purchasing high-quality stainless steel cups or mugs as they are non-porous, making stubborn stains unlikely.
Regularly cleaning cups or mugs can help prevent coffee stains from becoming entrenched in the material. Let’s review some of the best ways to remove coffee stains.
Five methods to permanently remove coffee stains
The following five methods should remove coffee stains from mugs once and for all. (Or at least until the next time you drink coffee, in which case you’ll need to repeat these steps.)
Method one
What you will need: Baking soda and water.
What to do: Make a paste by mixing equal parts baking soda and tap water. Apply the paste to the stained areas of the cup, rub gently with a sponge or brush, then rinse thoroughly.
Method two
What you will need: White vinegar.
What to do: Soak the coffee-stained mug in a mixture of white vinegar and water for a few hours. Next, scrub the stains with a sponge or brush, then wash the cup with dish soap to eliminate the vinegar’s acidic taste and pungent odor.
Method three
What you will need: Lemon juice and salt.
What to do: Make a mixture of lemon juice and table salt. Gently rub this mixture into the stained areas and then rinse thoroughly. Next you will need to wash the mug or cup with dish soap and water to eliminate the lingering lemon taste or smell.
Method four
What you will need: Baking soda and white vinegar.
What to do: Sprinkle a few teaspoons of baking soda inside the mug or mug, gently pour in the white vinegar and let the mixture sizzle. Once evaporated, rub the stained areas with a sponge or brush and rinse thoroughly.
Method five
What you will need: Denture cleaning tablets.
What to do: Denture tablets clean cups as well as clean teeth. Fill the stained cup with warm water and add a denture cleaning tablet, making sure to add enough water to completely cover the coffee stains. Let it sit for a few hours, then scrub and rinse as with the other methods.
As with anything, a little effort and time will go a long way in making your mugs sparkle. These tips will work on any glassware material and can even be used for tea stains. Feel free to repeat any of the above processes as needed to eliminate stains.
For more cleaning tips, you can also check out how often should you clean your makeup brushesand the the best way to machine wash sheets and bedding.
Frequently asked questions
What causes coffee stains on cups?
There are compounds called tannins in coffee beans, and when these beans are brewed, the tannins begin to stick to the surface of cups, mugs, and other containers they come into contact with.
Why do stainless steel cups stain less?
One of the factors that determines how much tannins stick to your cup is how porous the container is. Plastic, terracotta and stone cups will absorb tannins and stain very quickly. High-quality stainless steel is much easier to clean, as tannins are less likely to stick to surfaces.
