Can you Put Coffee in a Tumbler? Can It Damage it?

You’re in a rush this morning and you won’t have time to drink your coffee at home. You usually transport coffee in a travel mug, but that’s in the dishwasher. All you have is your favorite tumbler. Will the hot coffee damage the tumbler or can you safely carry coffee this way?

Yes, you can put coffee in a tumbler, be it hot or cold, and it should not cause damage. Some tumblers can maintain the coldness of a beverage for up to 12 hours and the warmth of a beverage for up to six hours.

If you want to learn even more about drinking coffee from a tumbler, you’ve come to the right place. In this in-depth article, we’ll talk about different tumbler materials and whether coffee has any effect on them. We’ll even discuss if stainless steel tumblers can change the taste of your coffee, so make sure you keep reading!  

Can You Put Coffee in a Tumbler Without Causing Damage?

What most people worry about when using a tumbler for coffee is that the caffeinated beverage is going to erode the tumbler material until your container is unusable. 

Coffee is certainly acidic, but not enough that it’s going to eat through a fairly durable tumbler. If that was the case, then that plastic travel mug that’s sitting in your dirty sink wouldn’t be a viable option for transporting coffee, yet it is. You also wouldn’t be able to go to your favorite café and have them serve you coffee in paper or cardboard cups. The acidity of the coffee would burn right through the paper!

The standard pH for a cup of coffee depending on how you like it is anywhere from 4.85 to 5.10. That may sound acidic, but the acidity scale starts from 1.1 and goes to 7.0, so coffee is about in the middle, a little past that. 

The gastric acid your body produces is much less acidic than coffee, as is lemon juice, apple juice, and tomato juice. Yet milk is even more acidic than coffee if your coffee’s pH is 5.0 since milk’s pH is 6.0.

Okay, but what if you like milk in your coffee? Since it’s so acidic and coffee is too, if you combine the two liquids, is a tumbler still a safe option? Yes, it is. 

Yeti mugs, which have a double wall insulation, will keep cold drinks nice and frosty for six to 12 hours. For hot drinks, a tumbler can retain heat for four to six hours, which is not too shabby!  

When possible switch out your metal tumbler for either glass or ceramic.

Does a Stainless Steel Tumbler Make Your Coffee Taste Funny?

One thing that you’ve always heard about stainless steel containers is they can alter the taste of your beverage. Coffee has a strong enough flavor on its own, but if you pour it into a tumbler, you want to enjoy the coffee taste, not metal. 

As a stable compound, stainless steel doesn’t react chemically to the liquids that go into a tumbler, even if those liquids happen to be steaming hot coffee. Yet if you use a stainless steel tumbler for coffee, you may taste a metallic flavor in the tumbler. Why? There’s two reasons.

1. Tumbler is Cheap

One such reason is that your tumbler is cheap and the metal has begun to tarnish. When tarnishing occurs, the metal’s outer layer corrodes. This can happen to many types of metal, including neodymium, magnesium, aluminum, brass, copper, and more. 

You can usually tell when metal has tarnished because it develops a coating in a distinct black or gray hue. Yet let’s be real, you can’t easily see inside a metal tumbler where the corrosion might have occurred, so you really only have the taste to go off of. 

And yes, tarnished metal does have more of a metallic taste thanks to the corroded metal. Drinking coffee from a corroded tumbler isn’t dangerous for your health, per se, but your taste buds will be none too pleased. 

2. Tumbler is Porous

Another reason your stainless steel tumbler could taste metallic is due to how porous it is. The smoother the cup, the fewer the pores. By brushing the interior of a tumbler for texture and appearance, which is something that manufacturers often do, the porosity of the stainless steel increases. Open pores can collect and hold onto flavor.

Some stainless steel tumblers don’t necessarily start out porous, but over time, they become that way. Scouring at your tumbler with a rough scrubber brush or an abrasive sponge is a great way to force the pores open. 

We’re not saying you shouldn’t clean your tumbler, as that would be ludicrous, but you certainly want to take a gentler approach to cleaning it going forward, such as a hand wash. Also, buy tumblers with mirrored or electropolished interiors, as these are nonporous.

Are Plastic Tumblers Safe to Use?

Perhaps your tumbler isn’t stainless steel but plastic instead. This is dangerous for many more reasons than a funky taste lingering in your tumbler. 

Plastic cups, especially the disposable ones that your favorite coffee chain might use, are likely made of polyvinyl chloride or PVC, a low-cost type of plastic. Yet the cup isn’t all PVC. It also includes a variety of additives to give the plastic more weight.

These additives can include dioxin, vinyl chloride, phthalates, formaldehyde, bisphenol A or BPA, and styrene. Let’s talk about each of these chemicals now.


The chemical group known as dioxins are known carcinogens that can also affect hormonal balance, immune system health, human development, and reproductive health. Once dioxins go into the environment, they often stick around for a very long time. That’s why they’re called persistent environmental pollutants or POPs. 

Vinyl Chloride

The flammable, colorless gas known as vinyl chloride is a common manufacturing material for kitchenware, car upholstery, wire coatings, and PVC pipes. Prolonged exposure could lead to the development of leukemia, lymphoma, and lung, brain, and liver cancers, specifically the liver cancer called hepatic angiosarcoma.  


Another dangerous chemical group, phthalates are still used in all sorts of everyday products, among them perfume, shampoo, soap, aftershave, hair spray, nail polish, food packaging, lubricating oils, detergents, and toys. 

Phthalates can cause a variety of health defects, including reduced male fertility, reproductive developmental issues, autism spectrum disorders, behavioral problems, neurodevelopmental problems, lowered IQ, type II diabetes, obesity, breast cancer, ADHD, and asthma. 


You know of formaldehyde as an ingredient that preserves dead bodies, but did you know that it’s also in some insulation, paper products, permanent-press fabrics, adhesives and glues, fiberboard, plywood, and particleboard? 

Breathing in enough formaldehyde could lead to death. Exposure to smaller quantities can cause skin irritation and breathing issues. 


An epoxy resin and plastic product, BPAs are incredibly damaging to our health, possibly leading to the onset of cardiovascular disease, type 2 diabetes, metabolic disease, childhood asthma, reproductive issues, and Alzheimer’s.  


The sweet smell of styrene, a liquid with no color, belies its health risks. This organic compound can cause peripheral neuropathy, reduced hearing, and depression from long-term exposure.

These chemicals are more likely to be found in plastic Solo cups and other cheap plastic drinkware than a plastic tumbler. That said, BPAs are common in many plastics. Even if your tumbler says it’s BPA-free, that doesn’t necessarily mean that it is.

The only way to be completely sure that your tumbler is safe for use is to turn it over and look at its recycling code. The code will contain a number 1 through 7. If it’s a 3, then the tumbler likely has BPAs in it. If it’s a 7, that can also be the case. It’s only the numbers 1, 2, 4, 5, and 6 that are truly BPA-free. 

Click the link to read more on the effects of plastic on your health.

How to Wash a Coffee Tumbler Without Causing Damage?

It’s best to hand wash your tumbler soon after you finish your drink. Use warm soapy water to protect the powder-coated exterior. If your Tumbler is not rinsed asap, and creates a stain in it, don’t be temped to use bleach. The residue is harmful to you and causes damage to the tumbler itself.

If your tumbler has a straw lid, we recommend not using for hot coffee, although cold or iced coffee is fine. A magslider lid is preferred, but it’s likely not to be leak proof.

Final Thoughts 

Putting coffee in a tumbler is possible without causing damage if you can’t drink your cup of joe before you have to leave for work. Stainless steel tumblers can sometimes corrode, which can affect the coffee flavor, so invest in a high-quality tumbler. Make sure yours is electropolished as well so it’s nonporous.

Plastic tumblers are dangerous for the bevy of chemicals they could contain which can affect your health in all sorts of ways. We hope this article has caused you to rethink your coffee drinkware so you can make smarter health choices! 

For ways to keep your coffee warm outside, click here.

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