Gruner veltliner grapes on the vine in Austria. (Austrian Wine Marketing Board/Faber)

Wine has always been governed by fashion — just like lapel widths, hemlines and shades of lipstick. Consider the trajectory of gruner veltliner. Nearly 20 years ago, gruner veltliner was the new black. Then about 10 years ago, Austria’s premier white wine was dismissed as a passing fad. Now, the fickle in-crowd of sommeliers and wine writers has “reconsidered” the variety and settled on the term “classic” to describe gruner veltliner — as if it were a Brooks Brothers navy blazer or Chuck Taylor All-Stars.

I want to be clear about one thing: I am not fickle. I have always loved GV. I love how diverse, how unpredictable, its mood and character can be, sometimes rich and aromatic, sometimes crisp and mineral, often peppery or spicy, and always lively, with big flavor without being too fruity. I love how friendly it is with food, how it lets the food do the talking, and how it pairs with just about everything, from fried chicken to barbecue to guacamole to sushi to pad thai to tandoori. It even plays nicely with spring vegetables, like asparagus, which notoriously don’t get along with wine.

In the late 1990s, gruner veltliner seemed to appear out of nowhere, the archetypal “stranger comes to town” story, and it dominated turn-of-the-century wine lists. People started referring to it by the nickname “Groo-Vee” or by its first name only, “Gruner” — like Prince or Cher. Or perhaps more like Björk. “Gruner,” in fact, simply means “green,” referring to the green variety of the veltliner family of grapes.

Yet as the aughts wore on, cheaper and cheaper gruner veltliner started appearing on shelves, much of it in oversize liter bottles. By 2006, Food & Wine magazine asked, “Is Gruner a Great Wine or a Groaner?” By the late 2000s, it had ceased to be cool. The new wave of hipster sommeliers discovered orange wines or rediscovered Mosel Riesling or Loire chenin blanc or sherry. Or they moved on to sake or mezcal or other drinks — some of which will also eventually face the vicious cycle of hype and backlash.

Then, about four years ago, wine’s gatekeepers and critics began talking about gruner veltliner’s “ageability” and “versatility” and “value.” And Groo-Vee didn’t go by nicknames anymore. It was sort of like when your old college friend Jimmy gets a good job, starts wearing a suit, and now wants to be called James.

In researching my book, I spent a good deal of time in Austria, tasting gruner veltliner all along the Danube. As I moved from Kremstal to Kamptal, from Weinviertel to Wagram to Wachau, what struck me most was that the better producers seemed determined to evolve the grape far, far away from the “Groo-Vee” vibe and to climb the ladder toward becoming a truly Serious Wine.

I visited the tasting room at Hirsch, with its epic views of Heiligenstein and Lamm, two of Austria’s most prestigious vineyards. In 2010 — right around the time the “Groo-Vee” trend was crashing in the United States — both were among the first vineyards in Austria classified as erste lagen or “first growth,” signifying the country’s finest terroir. This is similar to Bordeaux’s premier cru or Burgundy’s grand cru or Barolo’s crus. Classifying cru seems to be an obvious first step that any region takes when it moves toward a Serious Wine. If gruner veltliner is meant to be taken as seriously as nebbiolo or pinot noir, the gatekeepers and collectors need to be assured that the grape shows off myriad expressions of terroir — which it does.

One late afternoon, I tasted with another legendary Wachau producer, Emmerich Knoll. One of the greatest white wines I’ve ever tasted was a 1990 Knoll gruner veltliner that I’d bought in 2014. If there was any question that gruner veltliner can live for decades, that 24-year-old Knoll wine put it to rest. Knoll contended that gruner veltliner’s greatness lies in its diversity: You can’t pin it down to one flavor or aroma, that its character and personality change depending on where it’s grown. “You can taste 10 gruner veltliners and still cannot say, ‘I know what gruner veltliner tastes like,’ ” he said. “It’s the complete opposite of chardonnay.”

I tasted with Johannes Hirsch in Kamptal, a 40-something like me, who has been on the cutting edge since the original rise of GV. He was one of the first, for instance, to use screw caps to bottle his best single-vineyard wines. Hirsch showed me his new, minimalist labels. Until recently, Hirsch’s labels on his entry-level wines featured whimsical cartoon deer, the Austrian version of the funny “critter label” trend begun by mass-market producers such as Yellow Tail. But not anymore.

“People see a fun label, and they think it’s a supermarket wine,” Hirsch said. “I don’t want to say this isn’t a fun wine. But there is serious wine in this bottle.”

Hirsch’s gruner veltliners — which he gently ages in large oak casks as well as stainless steel — were wonderful in 2006, and over a decade later they still are amazing. Hirsch wines begin in precise, soothing tones, but they finish in a crescendo — full-bodied, deep and powerful. One of my favorites was from its Grub vineyard: It was floral and fresh, with a hint of smoke on the nose, but then finishing fleshy, ripe and bone dry. It lingered like some distant memory of an ideal summer night, peaches grilled over a campfire in a wildflower field.

Hirsch talked about the challenges gruner veltliner faces on the road to becoming a Serious Wine. “Gruner veltliner is still a foodstuff to us,” he said. “It’s not yet considered a luxury product. We’re still decades behind. Collectors still don’t have the self-confidence to say, ‘I like this. I’m buying this and not Burgundy.’ ”

That, of course, is the conundrum: A Serious Wine is, among other things, wine that ages. But how will you ever know if it ages unless it’s taken seriously enough to age?

This piece is adapted from Wilson’s new book, “Godforsaken Grapes.” He will sign copies of it at 3 p.m. May 19 at Maxwell Park wine bar. Wilson will also join our live Free Range chat with readers on Wednesday at noon.