(NBCNews) - Glug!

Now that the nation's millennials are all officially 21, this 79-million-strong crowd of tastemakers is starting to shape the nation's appetite for wine — buying more per person, spending more per bottle, and spurring the wine industry into finding new and innovative ways to capture this dominant market share.

Millennials (now between the ages of 21-38) consumed 159.6 million cases, or 42 percent of all wine drunk in the U.S. last year, according to a recent survey by theWine Market Council. And they're not afraid to splurge, either — the survey showed that 17 percent of millennials who drank wine spent over $20 per bottle, as compared to only 5 percent of baby boomer wine lovers.

But they're also a fickle bunch, preferring to look farther and wider to get their buzz on.

"It's not an exaggeration to say the millennial American consumer has the most varied set of tastes of any wine drinker in history," wrote Wine Spectator. Millennials generally favor new-world producers such as Chile, Argentina, and New Zealand; and, in step with their general trend of bucking the general trend, millennials are the least likely demographic to purchase America's favorite wine — a Californian red.

And, of course, since millennials love wine, there's an app for that. From wine delivery to wine clubs to a portable sommelier, this burgeoning demographic has yielded its own cottage industry of oenophile-related services. Delectable is a kind of Instagram for wine lovers, Drizly is one of many apps that bring booze to your doorstep within an hour ("Get the door, it's the liquor store!"), and VinoCellar helps you organize your wine cave.

"We are definitely seeing fast growth for other regions," Courtney Quattrini of wine app Vivino told NBC News in an email. "We know millennials are less brand agnostic and like options and variety."