Last Updated on April 19, 2022 by Practical Cooks
The coffee cup that you typically receive when you order coffee on the go is a paper cup with a disposable plastic lid. However, paper isn’t the only material you have to be concerned about. There’s also a wax film lining the inside of the cup, which prevents the coffee from seeping into the paper, and keeps the paper from getting soggy.
So, can you microwave coffee cups?
Microwaving a coffee cup can allow toxic chemicals to leak into the beverage. Additionally, the glue that keeps the cup together at the seams may melt and cause leaking from the sides and the bottom of the cup.
Your coffee may taste different because of the softened wax coating, the melted glue, and even the paper burns. Lastly, because most paper cups use polyethylene (a type of plastic), putting them in the microwave is a safety hazard.
What Do Paper Coffee Cups Contain?
While paper coffee cups seem convenient for transporting around while you’re busy during the day, they aren’t a good drinking vessel, nor are they suitable for reheating the coffee in the microwave.
You also can’t recycle them with other paper products because they are technically coated in plastic, as much as five percent in every cup. Harmful chemicals like this, along with the glue discussed earlier, can weaken the body’s system and have detrimental effects.
One study concluded that putting a product that contains plastic into the microwave may initiate estrogenic activity in the body. This side effect can play a role in obesity, reproductive organ functioning, and additional health complications.
What Different Types of Coffee Cups Are There?
Even though most coffee cups are made from paper that uses a plastic or wax lining on the inside and outside to make it waterproof, other options are available.
- Metal coffee cups
- Glass coffee cups
- Styrofoam coffee cups
- Regular foam coffee cups
- Ceramic coffee cups
These materials can present different problems when you place them in a microwave.
Above all, do not put metal or stainless steel coffee cups in the microwave because they can damage it and cause a fire, and do not microwave foam because it can melt. The other materials may or may not be microwave friendly, which is why it is essential to read the label before trying.
How to Choose a Good Reusable Coffee Cup Instead
Here’s how you can choose a safe and reliable coffee cup that won’t be a health hazard if you need to pop it in the microwave:
Choose a BPA-Free Cup That Is Food-Grade Safe
Keep in mind that heat produces chemicals that seep into the foods and liquids you consume. First, you want to find a tumbler or a coffee cup that’s safe by ensuring that it is BPA-free. Bisphenol A (BPA) is an organic compound known to adversely affectour body’s endocrine system.
Your Cup Maintains a Warm Temperature for Hours
Your hot coffee should be warm for hours with no problem, or a cold iced coffee drink should stay cool. Make sure you search for a cup that supports hot and cold beverages if you prefer both.
It Comes in a Convenient Size
There’s a chance that you only need a small amount of coffee to fuel you through the morning. Or perhaps you’re on the other end of the spectrum, and you like one big cup every day.
Whichever is your preferred size, procure a tumbler or mug that can accommodate the amount of liquid you plan to drink. For example, a small cup may be sufficient for you.
On the other hand, perhaps a large cup is best for you because you have the freedom to fill it with less liquid when you’re not planning on consuming lots of joe.
It Comes with a Lid
Portability is the main selling point when looking for refillable coffee cups. The lid is crucial to cover the drink, preventing the heat from escaping prematurely.
Additionally, with a lid, spills can be limited and controlled. The top can also keep particles and insects from flying into your cup, especially if you’re drinking coffee outdoors.
Below you’ll find the answers to the most commonly asked questions as it pertains to putting your coffee cup in the microwave:
1. Can cardboard coffee cups be microwaved?
It is not advised that you microwave paper cups. The process of microwaving the paper cups results in the cardboard material breaking down and could potentially release harmful chemicals into your coffee or possibly catch on fire. The paper cup will likely warp and become damaged.
2. What happens if you microwave a ceramic mug?
Typically, ceramic mugs will have labels stating that they’re microwave-safe or not used in the microwave. Yet and still, the glazed finish that’s common to ceramic containers can contain lead or other metals such as arsenic. These substances can contaminate liquids microwaved in such a mug.
3. Can you heat Starbucks cups in the microwave?
All Starbucks paper cups have a “Do Not Microwave” label on them. You cannot reheat the cups in the microwave due to their internal plastic lining. Therefore, empty the remaining drink into a microwaveable mug or cup. Then reheat the contents safely.
4. Can you put a styrofoam cup in the microwave?
There is some apprehension when it comes to microwaving polystyrene containers. This concern exists due to a substance in the styrene material, which human and animal studies have linked to cancer.
Additionally, you wouldn’t want the plastic substances to break down and leak into your food. With that said, if the styrofoam cup says this is microwave safe, then you can microwave your beverage of food in it.
5. What happens if I microwave a metal coffee cup?
A microwave has a part inside called a magnetron. When you place metal inside a microwave, the metal has lots of electrons that get pulled by the microwave magnetic grid, and it can cause a thin sheet of metal to heat up so quickly that sparks could fly and burn the cup completely.
So, Can You Microwave Coffee Cups?
Always check the label when you’re trying to reheat your cup of coffee and are unsure whether the material is microwave-safe. In general, paper, plastic, and metal should not get microwaved, as these materials can leak chemicals into your beverage.
Glass, ceramic, and styrofoam may or may not be safe, depending on the manufacturer’s label. Selecting high-quality reusable cups made from safe and recyclable materials is always the best option.