Article from Food & Wine by Brian Freedman

The most important aspect of tasting wine like a professional? Don't ever stick out your pinkie finger, take a sip, and then begin speaking poetically about all of the obscure nuances you perceive in the liquid. Seriously. You'll look and sound ridiculous, and even worse, pretentious. And despite that old-school reputation for snobbery and judginess that sommeliers and wine pros have historically had, that's just not how the vast majority roll anymore.

Now that we can proceed with our collective pinkie fingers and pretensions safely tucked away, the question remains: How do you taste wine like a pro? Also: Why would you want to? After all, there's no formalized routine that most people go through when drinking most other beverages, so why is there so much swirling and sniffing and spitting when it comes to fermented grape juice?

The answer is relatively simple: Because wine possesses such a wide range of flavor and aroma compounds that you want to do everything in your power to maximize your perception of the broadest possible swath of them. And that means –– you guessed it –– swirling, sniffing, and the rest.

Here's how it works. Once the wine is poured, you'll want to swirl it in your glass, tracing small circles with the base in order to create a little wine whirlpool in the bowl. This accomplishes two main things. First, it brings oxygen into the wine, which will help open it up, allowing it to more fully express itself. Think of it as the wine equivalent of stretching before a run. You don't technically have to do it, but the experience is a whole lot more pleasant if you do. The second benefit is creating a fine layer of wine around the inside of the bowl, which gives your nose more surface area from which to perceive aroma. And since the majority of what we taste is actually a consequence of what we smell — thanks, olfactory bulb! — then everything we can do to maximize aroma is a good thing.

Once you've sniffed the wine (combining a mix of short, sharp sniffs and deep inhales), then it's time to slurp. Technique is key here: You don't want to do your finest impression of the guy in the old Listerine commercial, swishing it all around your mouth. First, that looks ridiculous, and second, because it'll overwhelm your palate with tannin (if any), acid, and the rest. Instead, take a small sip, make a face like you're going to whistle (in other words, purse your lips), and draw air in over the wine on your tongue, so that it flutters between it and your soft palate. This will throw the layers of the wine's flavors into even sharper relief, allowing you to see if it's flawed in any way, and also to more fully appreciate the nuances it offers.

The final step is generally only reserved for professionals who are tasting many wines side by side, which is spitting. There are days when I start tasting before nine in the morning, and if I didn't spit, I'd be a blithering mess by lunchtime. Spitting, in other words, is a key to both my professional success, and to my ability to function past noon. But if you're tasting a reasonable number of wines, and you have nowhere to go afterward, there's really no need to spit.

It's the one aspect of my job that I don't love: Spitting out car payments' worth of wine every week.