You can't judge a book by its cover, but can you judge a coffee without even tasting it first? Not always, but surely it's possible sometimes. Here are some visual clues to help you tell the good from the bad and the ugly.
In the photo above, we see the difference between a well-made cappuccino topped with silky microfoam and, frankly, the kind of crappuccino you'll find brought out by servers at some of the finest restaurants all over the world: A dense chaos of dry foam plopped atop a badly pulled shot of weak espresso. The difference is more than just visual, though the sight alone tells you something about the taste.
While the coffee on the left will have a balance of milk and espresso flavor (a little bit of both with every sip) to complement its velvety texture, the other one will lack sweetness thanks to the overcooked milk foam, and the drinker will have to slurp through all that heavy fluff in order to reach the coffee flavor—such as it is—underneath.
Is there anything you can do to save such a sad capp? Unfortunately not much, save perhaps a vigorous stir to mix the coffee and froth, and a bit of sugar to make up for the natural sweetness that won't come through in that disastrous dairy. (And maybe stick to drip coffee next time.)
Oh, dear. Espresso is tricky, because even the good looking shots can sometimes taste pretty bad. It's very hard to truly judge a cup by appearance alone. But there are some clues that might lead you in a general direction—which, in some cases, might be toward the exit.
The easiest way to snap-judge a coffee is to check the color and elasticity of the crema. In the photo above, you can see how washed out and pale the top of the left shot looks, as opposed to the darker, more viscous head of foam on top of the right one. The former might mean that the shot sat long enough for the crema to almost completely dissipate (maybe five minutes or so), or that the barista used too coarse a grind or far too much brew water. In any event, the result will most likely be a bitter, thin shot lacking any sweetness or character.
The best way to prevent winding up with an "espresso" like that watery swill above? Keep your eyes peeled: Checking out what other customers' drinks look like might prevent you wasting your hard-earned dough on a bit of brown caffeine water.
What other tips do you have for judging a book by its proverbial cover—or a shot by its crema?