When It’s Time to Buy New Coffee Cups
When It’s Time to Buy New Coffee Cups
Form Follows Function
Including an Interview with Fabiana Carvalho
I had four coffee cups that I loved, and, gradually, all but one were broken. They were — the survivor is — Japanese, not expensive, maybe meant for tea, made of porcelain, with a heavy bottom and straight sides that angle slightly outward, ending in a thin lip. The capacity is 250 ml, or a little more than one US cup. Looking online, I can’t find any evidence that those cups are still made, or ever were for that matter. The design appealed to me: large enough for one strong cup of coffee, heavy enough to hold heat, with a thin lip, white inside with light blue outside, which I always thought set off the red-brown of coffee. Not being able to find identical replacements, for several years I did nothing except treat that last cup very carefully. I kept thinking, what am I going to do when it breaks, and what besides some random sports mug do I offer anyone else?By Edward Behr
When I began to look, I found that, oddly, specialty roasters don’t especially promote and sell cups designed to enhance the taste of the coffee. Half a dozen or more (nonroasting) companies make such cups, and some roasters sell one or another, but there’s no consensus, no great praise focused on any particular one.
The ideal cup or mug probably lies in the eye of the coffee-drinker — especially for many Americans, size is key and personal, some keeping and carrying a drink like a friend — but a few things can be said. The cup should be either insulated or thick enough to hold some heat. Among materials, metal loses heat rapidly, and although I don’t find scientific evidence one way or the other, I suspect most people don’t like drinking from it, or from plastic. Glass is a worse conductor of heat than ceramic and therefore would be a better insulator, except that ceramic materials have pores, so they insulate better after all. Apart from the material, you probably want a cup with a white interior so you can see the color of the drink. A handle may be convenient, but some people feel it only gets in the way: if what you like about coffee is the immediacy, you probably enjoy feeling the heat.
Then there’s the shape, which until recently I had hardly thought about. Wine glasses are made in different shapes to bring out the qualities of different wines, so it seems reasonable to think that the shape of the cup affects the taste of the coffee. We fill wine glasses only partway to allow space for the aroma to gather, but most coffee is drunk hot, which makes the aroma much more volatile; we’re not in the habit of swirling coffee like wine to coax out more aroma. But maybe it would be worth having extra space to hold it. Personally, I like a thin lip, like that of a good wine glass, whose thinness, wine professionals agree, provides a better taste, even if the reason is a mystery.
Espresso is set apart by its intensity, and maybe the shape of the cup makes less difference. Because the small amount of espresso in a cup cools quickly, the cups are kept warm on top of the machine. They’re usually thick, which makes them less breakable, but at least in Italy an espresso is drunk almost immediately, so whether the cup holds heat doesn’t much matter.
I sent my tentative thoughts to Peter Giuliano, the executive director of the Coffee Research Foundation, suggesting that an ideal coffee cup might perhaps be ceramic, thick enough to hold some heat, have a smooth surface and a thin lip. He emailed back: “For coffee consumers, temperature is especially important as it drives both sensory perception and the sense of warmth that many people seek for their coffee.” He said, “Most coffee experts, in my view, favor heavy bowl- or cylinder-shaped coffee cups made of thick white ceramic. These cups are generally filled 4/5 of the way to provide aromatic headspace.” He commented, “It’s funny you mention a thin-lipped cup, as this is my personal preference. However, this preference is not generally shared. In fact, for the reason mentioned above, thick-lipped cups are often favored over thin-lipped ones.” He referred to Charles Spence, professor of experimental psychology at Oxford and the most prominent of the cross-modalists, who study the interaction of different sensory modes — sight, sound, touch, taste, and smell — not just in connection with food and drink. And he urged me to get in touch with Fabiana Carvalho, a neuroscientist who has worked with Spencer, particularly on coffee, and has done studies of the effects of different shapes of cup, using the ones designed by the Oslo roaster Tim Wendelboe in conjunction with the manufacturer Figgjo.
To give an idea of the sometimes-unexpected nature of the work, one study compared the effects of a smooth and a rough ceramic cup. Where coffee professionals rated coffee from the rough cup as more acidic, amateurs rated coffee from the smooth cup as sweeter, and both found the rough cup left a drier aftertaste.
I posed questions to Fabiana Carvalho by email.
Why did you choose the Figgjo cups for your 2018 study on the influences of shape?
We chose them for several reasons. First, they had been developed by coffee experts (Tim Wendelboe team), together with designers at Figgjo, having in mind the creation of functional cups (not only aesthetically pleasing ones) in order to enhance the coffee drinking experience. And they were already in the market.
Second, they were perfect for a scientific experiment because (1) the three cups could be seen as representatives of three main/common shapes in drinking vessels: the ‘open’ shape, the ‘enclosed’ shape, the ‘indentation’ shape; and (2) they only vary in shape — all other features are constant amongst them: Material, colour, texture, size (volume), height, weight, thickness of rim, which is mandatory for research assessing the effect of shape.
In that study, do you believe it was the width of the top of the split cup — the wider stream of coffee entering a taster’s mouth — that gave tasters a stronger impression of sweetness and acidity?
We did not measure how the liquid entered the tasters’ mouths, so we cannot infer this could be the case. In the world of wine, some highly-respected authorities (e.g., Grainger, 2009; Peynaud, 1987) have suggested that glasses with different shapes may interfere with oral sensation as a result of a particular flow pattern of the wine across the taster’s tongue. These views account for either narrow and wide opening glasses, or the difference between thin and thick rims. They assume that the physical shape of the glass helps direct the liquid to particular locations on the surface of the tongue, and that this variation in flow patterns would lead to differences in the perception of specific taste compounds. However, detailed investigations that could provide convincing evidence to support such assertions are still missing. Namely, that the flow properties really do differ, or that any such differences really do impact the multisensory tasting experience (based on the oversimplified traditional tongue map).
In fact, both Thomas Hummel and Charles Spence have discussed that variations in flow pattern across the tongue, as a factor, should have a much smaller effect than other factors such as crossmodal correspondences, individual tongue movements or variation in sensitivity thresholds from taster to taster.
Wine glasses are often cited as a point of comparison in talking about the effects of different shapes of coffee cup. But does the heat of hot coffee make the aroma so much more volatile that the shape of the cup matters much less with coffee than with wine? That is, does one really need a large headspace to capture the aroma of coffee?
For specialty coffee, I would say both the shape and the headspace matter. Specialty coffee is not usually consumed hot (above 65C [149 degrees F]), and anyhow the water steam can prevent certain volatiles from being perceived. We haven’t tested the effect of headspace in coffee, but I could say from observation and discussion with coffee experts that some specific aroma notes, such as the floral ones, are better identified with a headspace that allows a gentle swirl of the coffee.
The shape affects the perception of the overall attributes of espresso as well.
A coffee cup with a thin lip seems to me to make coffee taste better, the way a thin wine glass with a thin lip is commonly believed to enhance wine. Is there any scientific work that explores the effect of thinner vs. thicker lip? (For its thin lip, I really like the Dibbern coffee cup, which is absurdly expensive and doesn’t have an enclosed headspace.)
No, there’s not. And I have been planning to test this effect for a long time (since before the pandemic lockdown). From what I have been observing and [from] talking to experts and consumers for a while, the thickness of rim seems to be a hedonic driver (some people simply find it more pleasant to drink coffee from a cup with thin/thick rim). It would be interesting to test whether the rim would impact some sensory attributes (say, mouthfeel) that would be preferred by the consumers, and then the rim would actually be a mediator factor.
Thinking of your study on the effect of cup color, for a professional is a white color perhaps the most neutral in terms of expectations and actual experience, or is a truly neutral color perhaps not even a possibility?
Yes, the white could be considered ‘neutral’ in this case since it’s the most common colour for ceramic cups. In our study, we used it as a baseline.
What do you believe is the most important aspect of coffee cup shape that has yet to be studied?
I would say size (to test for the effect of headspace) and the thickness of the rim.
So what should you buy? Before my exchange with Fabiana Carvalho, I’d started looking for cups that imitated my surviving favorite, although that meant no closing in toward the top, no headspace for aroma. I tried the porcelain Base coffee cup, which holds about 250 ml and is designed in the Netherlands, but it’s so thin that just-brewed coffee makes the cup uncomfortably hot, and then the cup and coffee cool very fast. And with the cup’s lightness, drinking from it doesn’t feel special. (Four handleless cups are $68 from the US Serax website and €48 from the European site, plus shipping.) The thin-lipped, handleless Pure bone china “mug” made by the German company Dibbern also holds 250 ml, and it’s precisely made. Its elegant simplicity might strike you as ideal or else way too minimal. It’s thick enough to hold heat for as long as it takes me to drink the contents, and although the small base makes it a little tippy, I find it a pleasure. The stumbling block is the price. A single cup is $50 plus shipping from Gracious Style in the US or, among Europe sources, €32 from Dibbern itself. Anyway, neither of those cups is claimed to enhance taste and there’s nothing particular about them that would.
The shapes for which claims are made are generally aimed at people who drink only small amounts of strong brewed coffee or maybe go for lots of refills. They’re tasting cups rather than drinking cups, especially if you only half-fill them to leave headspace. Most are porcelain and come in white. A few have an outward-curving lip, which is atypical for a drinking vessel of any kind and sends, intentionally, a wider stream of coffee into your mouth. A pro wants a single shape so as to make equal comparisons, but some of the tasting cups come in sets of three or four different shapes meant to bring out the qualities of different beans.
I rule out glass for myself, but the two 150-ml coffee glasses from Kruve in Ontario are a useful point of reference. They’re made of double-walled (thus insulated), less-breakable borosilicate glass (the same as used for Pyrex). And they’re designed by engineers, focused on headspace, and enthusiastically geeky: “Scientifically designed to amplify or soften certain flavour notes, just like an audio equalizer, and put you in control of your sensory experience!” One shape is wide in the middle for a larger surface area, with headspace above, which “traps and circulates aroma, while softening acidity and enhancing sweetness.” The other allows less surface area and a narrower headspace: “This focuses and funnels the aroma, while enhancing acidity.” (For espresso, Kruve makes both a glass and a porcelain cup in a mini version of the larger-surface-area shape.) As I write, Kruve has the pair on sale for US$89.97, but I admit that, not liking glass, I haven’t tried them.
Espro, also Canadian and founded by engineers, produced four different porcelain cups, each holding about 325 ml and aimed at “coffee’s four most sought-after flavors”: cocoa, floral, fruity, and spicy, taken from the Specialty Coffee Association’s Coffee Taster’s Flavor Wheel. The lips are somewhat thin, and while the four shapes appear distinct side by side, each by itself just looks like another mug or cup. In tasting, I found the more enclosed shape offered a little more aroma and flavor. The set of the four was about US$80, but as I write the cups no longer seem to be available.
The trio of Figgjo cups, used in tasting studies, hold about 225 ml each. They are “open” (straight sides angled slightly outward, so the top is wider than the bottom), “tulip” (not that curvy a tulip, narrowing somewhat to the top), and the awkward-looking “split” (a spherical bottom with an open half-sphere on top, creating a headspace above a constricted waist). On the Wendelboe website, they’re about $14.50 each plus shipping (moderate even to the US).
Origami in Japan makes four basic shapes: the “aroma” has straight sides tapering in; the “barrel” is a short tulip; the “pinot” is bulbous with an outward-curving lip; and the “sensory” is bulbous with a narrower opening and an outward-curving lip. The first three come in either cup sizes, without handles, or in larger mug sizes, with handles. The “sensory” has no handle, an outward-curving lip, and is made in only a 360-ml size to allow headspace (and at the moment is sold out). The “barrel” is the shape most often cited and sold by US coffee people. It’s thick enough to hold heat, although the lip is also somewhat thick and the execution isn’t especially fine. The “barrel” cup, at 210 ml, which may hold a little less than you want, is about $20. The “barrel” mug, at 320 ml, is around $25 from various sellers.
At a guess, while we wait for more study, the ideal shape is a tulip, like most wine glasses, though it could be more angular (e.g., the Kruve), like some wine glasses. It’s worth saying, I think, that at breakfast, if you’re not in an analytical mood, an unusual shape may lack generosity or be annoying. As I probed, I realized that what I want for myself is not an organoleptically perfect cup (as a coffee pro would) but just the coffee equivalent of a decent everyday wine glass. I don’t enjoy the oddity of an outward-curving lip, and I’m leaning toward the Origami barrel mug, which, exceptionally, has options for a range of outside colors (see the full selection on Origami). Maybe, along with anything else, what you want is a little color.●
From issue 112The post When It’s Time to Buy New Coffee Cups appeared first on The Art of Eating Magazine.