Ceramics are one of the most common forms of coffee cups and I’d bet that not a single second goes by without someone, somewhere in the world, taking a sip of hot coffee from a ceramic mug.
I wonder how many of those people will put down their cup after that first taste, neglect it for a little too long, and return to a sad sip of room-temperature coffee.
This happens to me far too often! I love my ceramic cups as they don't affect the flavor of my coffee but do ceramic mugs keep coffee hot and if so for how long?
Ceramic mugs will keep coffee hot for longer than single walled stainless steel mugs, and about the same amount of time compared to glass mugs. Stoneware mugs will retain the heat longer because stoneware mugs are generally thicker than ceramic. Ceramic lined travel mugs keep coffee hot longest with double walled ceramic mugs being the next best option for heat retention.
Lets have a detailed look at ceramic cups and how good they are at keeping coffee hot compared to some other common alternatives.
What Is Ceramic and Why Does It Keep Coffee Hot?
Ceramic generally refers to any nonmetallic mineral, such as clay, that is fired at high temperatures. The different types of ceramic mugs are usually defined by the type of clay used and the temperature at which they are fired at.
When people say “ceramic mugs” they are usually referring to mug with thicker side that are opaque and fairly sturdy.
Compare this to porcelain or “fine china” which is made from a different clay and fired at higher temperatures. Porcelain is technically a type of ceramic but saying “porcelain mug” or “ceramic mug” almost always means 2 different things.
Stoneware mugs are another type of ceramic mug that tends to be thicker and is non-porous so it doesn't need to be glazed like ceramic mugs often do.
Ceramic mugs retain heat better that porcelain mugs mainly due to their thicker walls being better at insulating against heat loss. Ceramic mugs keep coffee hot similar to (or slightly long than) glass mugs – but this depends on the thickness of the ceramic and the glass mugs.
As a general rule, the thicker the ceramic mug, the better it will be at keeping coffee hot and the thinner the mug the faster your coffee will lost temperature.
Can You Put Hot Coffee In a Ceramic Mug?
Yes, you can safely pour hot coffee into a ceramic mug. Ceramic mugs can withstand extremely high temperatures and they do not leach chemicals or flavors into your coffee – making them one of the perfect choices for a coffee cup.
Unless the mug has been very poorly made (or been in the freezer) there is little to no chance of it cracking due to thermal shock.
If you are worried about the boiling hot beverage picking up any flavors from the porous ceramic; don’t. Another reason we use ceramic in coffee mugs is because ceramic will not absorb any flavor from the hot coffee nor impart any flavors to it.
Do Ceramic or Stoneware Mugs Keep Coffee Hot Longer?
If we were to compare the average ceramic mug to the average stoneware mug we would have to conclude that stoneware mugs keep the coffee hot longer. The reason however, is not due to the properties of the ceramic material vs stoneware.
Stoneware mugs are generally thicker than their ceramic counterparts, and this is the only reason that a stoneware mug will retain the heat inside for longer.
If you had a ceramic and stoneware mug each with the exact same thickness then they would keep coffee hot almost identically. The difference would be so small you'd hardly notice (if at all)
It again comes down to thermal conductivity, with the thicker walls of stoneware mugs being less thermally conductive and allowing less heat to pass through.
Double Walled Ceramic Mugs Keep Coffee Hot Longer
When comparing types of cups for heat retention, we find that regular ceramic mugs can keep your coffee warm for about 10 to 30 minutes whereas a double walled ceramic mug can keep your coffee drinkable for 1 to 2 hours.
In double walled mugs you have an inner wall that comes into direct contact with your hot beverage, and an outer wall. Between the two layers is an insulating layer of air.
The air layer acts as a buffer that slows the transfer of heat to the outer layer, which also offers an extra coat of insulation. This is why coffee can stay hot for so much longer.
Double walled stainless steel mugs usually have a vacuum between the layers. A vacuum is the best insulator so these types of mugs are even more effective at keeping the heat trapped.
You won't find a vacuum in double walled ceramic mugs though as the pressure would cause the ceramic to break.
How To Keep Coffee Hot In a Ceramic Mug For Longer
As we have seen, there is some room for improvement when it comes to ceramic mugs keeping your coffee hot.
Fortunately there are a few things you can do to stretch out your coffee time even more:
- Use a lid
- Use a mug warmer
When you pour hot coffee into a room-temperature mug the coffee immediately loses some of its heat to the mug. The mug warms up and your coffee gets colder.
If your mug was already hot, this would not be an issue.
An easy hack is to fill your mug with boiling water and let it sit for a minute. Once the mug is hot simply pour out the water and fill it with your coffee.
This way your mug can actually add some heat to your coffee when it is initially poured it and it'll slow down the cooling of your coffee.
Cup sleeves or tea cozies made from cotton or yarn are another way to add an extra layer of insulation to your mug. More insulation equals more heat retention.
Use a lid
Insulation is all well and good but most of your heat is going to leave the coffee through steam escaping out the top.
Commercially available plastic or silicone lids are a great way to trap the steam and thus the heat from escaping your mug.
Ceramic Lined Travel Mugs Keep Coffee Hot The Longest
Ceramic has a nice natural feel to it which makes it feel pleasant on your lips when you take a sip. Who wouldn’t want that same luxury when on the go?
Ceramic lined mugs allow the insulating power of a vacuum insulated stainless steel mug with the benefits of the fact that ceramics don't impart flavors into your coffee.
A ceramic lined travel mug just makes sense, and is actually the best option when wanting to keep coffee hot the longest and still have that ceramic feel.
Combining a ceramic inner lining with a stainless steel outer shell, coffee is able to stay hot for up to 8 hours. This article about the 8 best ceramic lined travel mugs is very informative if you are looking to buy one.
Ceramic is a porous material that has low thermal conductivity and thus will insulate your coffee to a good degree. Here are your ceramic options for keeping coffee hot, from best to worst:
- Ceramic lined travel mug
- Double walled ceramic mugs
- Pre-heated ceramic mug
- Regular ceramic mug