Can Glass Coffee Mugs Go in the Microwave?
For decades, people have unwaveringly heated their beverages —whether tea, coffee, hot chocolate or something else— in glass coffee mugs in the microwave. But can you really put glass coffee mugs in the microwave safely? It’s a good thing to be aware of when you are short on time and need to heat up your morning cup of joe quickly.
The Safety of Placing Glass in the Microwave
Traditional wisdom holds that conventional glass, china and glazed earthenware dishes are all microwave safe. However, microwave oven manufacturers do not recommend putting glass, glazed ceramics, or other unglazed ceramics in the microwave. The reason is that microwaves can quickly heat up any water molecules in the glass or ceramic and cause a sudden, explosive cracking or shattering of the cookware. This is especially true if the mug is made of thicker glass or if it has a shorter brim.
Types of Mugs Suitable for the Microwave
For safety reasons, you should only use mugs that are specifically labeled as “microwave safe”. You can often find these mugs in kitchen and cookware stores.
Considerations and Precautions
Here are some additional precautions you should take if you are using glass mugs in the microwave:
- Check the mug for any chips or cracks before putting it in the microwave. Any kind of defect could increase the chance of a sudden breakage due to the sudden heat generated in the microwave.
- Do not overheat the mug. When you start to heat the mug in the microwave, do not leave it unattended. Monitor it and take it out when it is heated to your desired temperature.
- Do not let the mug sit in the microwave after heating. Glass can retain heat for quite some time, even when it’s out of the microwave. Give it some time before handling it.
Bottom Line
Be sure to use mugs made from materials specifically labeled as “microwave safe” to avoid any risk of sudden breaking or cracking. And if you have any doubts or concerns, be sure to check with the manufacturer of the mug before you heat it in the microwave.
