Plus, how a smaller serving can make all the difference
By Anna Kocharian
The perfect cup of coffee may begin with fresh beans and a high-quality coffee maker, but the vessel from which it’s consumed can make the difference between a hot, aromatic brew and a lukewarm letdown.
If you’re a regular coffee drinker, chances are you already have a go-to. Maybe it’s a novelty diner mug you’ve had since college or one that’s basically a cereal bowl with a handle. Either way, you may have put more thought into the brew than the object it’s in. Let’s flip the script for a moment.
An electric or insulated mug can keep a brew warm for upwards of 12 hours, but sometimes taking a less utilitarian approach can have its benefits too. An important part of our taste experience is our culture and our force of habit, says David Latourell, coffee consultant and sales manager at the Specialty Coffee Association.
“Some of us drink our coffee on the way to work in the car. Some of us drink our coffee at the local diner. Some of us get our coffee from fancy coffee shops,” he says. “What we’re used to goes a long way in defining what we find pleasurable to drink from.”
Coffee cups come in a variety of shapes and sizes, from short and shallow ceramics to tall and double-walled glass mugs. But what’s the right choice when it comes to preserving the temperature and flavor of a brew? We turned to the experts to learn more.
The Perception of Taste
Our senses play an important role in how we appreciate a cup of coffee. Everything from the aromas delivered to our olfactory system to the temperature of the liquid and how it transfers from the vessel into the mouth—think the tilt of the head as the coffee enters—are all impacted by the shape, size, and material of the cup you’re drinking from, explains Latourell.
Photo: Getty Images
Ceramic cups can provide the weight that some look for or desire while drinking coffee, which in turn can bring a reassuring level of comfort and therefore higher perceived quality, says Yeekai Lim, founder of Cognoscenti Coffee Roasters, a Los Angeles-based coffee shop.
But the material can also impact the temperature of a brew. The more mass it has the more heat it will absorb, eventually reaching a point of equilibrium where it’s able to retain enough heat to keep the coffee warmer for a longer period, says Lim—in which case, a thicker ceramic cup would fare better.
In fact, Kaleena Teoh, co-founder of Coffee Project NY, prefers ceramic mugs for their texture and the ideal warmth that comes with holding a hot cup of coffee. When you compare glass, ceramic, and metal, chances are that ceramic options are better at heat retention, says Teoh. “Given the thickness of mugs made using those three materials, ceramic would probably be more comfortable to hold as well given that the material doesn’t heat up as much as metal or glass when you pour hot liquid into the cup.”
Glass mugs may be popular for aesthetic purposes. They’re usually a little more delicate and great for when you want to showcase the drink’s color and intensity, says Teoh. Their ability to retain heat is another plus, more specifically with the double-walled kind, where the space between the two layers of glass acts as an insulator. But while they may give off a refined look and feel, the material can also alter the perception of the coffee served.
Coffee brewed using thick paper filters by way of a Chemex will look quite lovely in a glass cup, says Latourell, while the same coffee brewed in a French press will appear slightly dirtier in the very same glass. Tasted blind, the coffees will differ in flavor because of their brew methods. “Yet, many people will be turned off by the murky French press coffee if they get a chance to see it clearly in the glass,” says Latourell, adding that they will most likely prefer it in a mug.
Interestingly enough, Lim has found that more expensive pour-over brews tend to be served in a glass carafe with a smaller glass cup, which can help dissipate the heat and reach optimal flavors more quickly.
Photo: Getty Images
The vast majority of our taste experience is smell, says Latourell, so, similar to wine glasses, the shape of a coffee cup or mug can either help or hinder the concentration of aromas and how they’re delivered to our senses. He points to Figgjo, a Norwegian company that produces cups tailored for brews with specific acidity levels and intensity of certain flavor notes.
The shape of the vessel will also impact the temperature of the brew and how quickly it cools down. Those with a smaller surface area will reduce evaporative cooling, says CR’s senior test program leader Bernie Deitrick. Meaning that the more narrow the mug is, the longer the coffee will stay warm. When comparing vessels that are equal in size, weight, and shape, glass and ceramic should perform similarly, says the testing expert. The reason is that they have similar thermal properties.
With non-insulated mugs, the best combination for keeping coffee warm is either going for a preheated heavy one or something with a cover. “If the mug is not preheated, then the lighter it is, the better, because the mug itself is heated up by the coffee, which cools the coffee down,” Deitrick says.
Photo: Getty Images
Tips for a Better Coffee-Drinking Experience
Watch what you pour. The amount of coffee poured into a vessel can make a difference in how it tastes. If you leave room above the brew, that would allow some of the aroma to be captured while you’re drinking it, explains Lim.
Think small. According to Deitrick, smaller mugs, with multiple small servings (rather than one big pour) can optimize the flavor and retain the heat of a brew.
Keep it clean. Material can impact the way coffee tastes if it is in any way contaminated with elements like soap residue, says Deitrick. Be sure to properly rinse out your mugs before using them.
Look for quality. When buying ceramics, Lim recommends avoiding cups that are porous—often a result of improperly fired ceramics—which could retain some byproduct or residual traces of old coffee or even soap.
Expert-Recommended Mugs and Cups
Want to sip like the pros? We asked them what they use at home.
Chemex Double Walled Mug, $23 at Amazon
Kruve EQ Glasses, set of 2, $50 at Kruve
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