You're taking a leisurely walk down the beer aisle, and see all of the familiar, usual suspects when it comes to beer styles. IPA. Oatmeal Stout. But then you see it..that mystery phrase. Grand Cru. It's on all kinds of bottles produced by various breweries around the world, but what does 'Grand Cru' actually mean in terms of the beer?The vague, short answer? It means nothing.Okay, I guess I should probably shed a little bit more light on the Grand Cru mystery. The term 'Grand cru', which is French for "great growth", is more traditionally and historically known as a label given to wine. It refers to the highest classification of French wine, and relates to the plot of land where the grapes are grown or, in relation to Bordeaux wines, the chateau at which the wine is made. Basically, think of it as the 'best of the best' in terms of wine.So what does any of that have to do with beer? Well..again, technically nothing. In the case of 'Grand Cru' being used on beer labels, we are simply talking about the adoption of a phrase for the purpose of marketing. Other products, like Valrhona chocolates or Remy Martin cognac, also use the phrase Grand Cru for these purposes. The big difference is that, in terms of wine, it's a phrase that is actually clearly defined and regulated. Everything else? Not so much.Beer writer Michael Jackson theorizes that the transition of the phrase Grand Cru from wine to beer may have first started to develop centuries ago when Belgium was under the rule of Burgundy. The seeds of appreciation for great food and beer were likely planted then, and led to the adoption of the term as Belgian brewers wanted to note their beers that were in the 'upper echelon.'So there it is. Grand Cru, as used in relation to beer, is just a name, not a specific style or designation of beer. In fact, if you were to grab 4 bottles labeled Grand Cru from 4 different breweries, chances are you'd end up with 4 considerably different beers. The common thought is that labeling a beer Grand Cru is implying that it is the brewery's 'best' offering, or an improved, modified or bigger version of a previously existing beer (take Rodenbach and Rodenbach Grand Cru, for example).One common thread that seems to exist is that the majority of the Grand Cru offerings you'll see tend to be Belgian or Belgian-style beers. For example, last year Great Divide released a Grand Cru, a Belgian-style Dark Ale that is big and boozy but with a nice rich sweetness to it. On the other end of the spectrum, Schlafly's Grand Cru (which is available year-round) is a much lighter offering. While still fairly high in ABV at 9%, this Belgian-style pale ale has fruit notes balanced with a bit of spice and funk. If you drank these two beers next to one another, they'd be remarkably different, yet both bear the name Grand Cru. And then there's North Coast, who released a Grand Cru that was a strange, champagne-like beer that was brewed with agave nectar and pilsner malt, then barrel-aged. An odd beer for sure, yet in my opinion, also oddly enjoyable. Throw in some of the wild/sour Grand Cru beers produced by breweries in Europe, and you have a wide variety of styles and flavor profiles, all falling under the same title.So when you're beer browsing, be wary if you are considering grabbing a bottle with the phrase Grand Cru smacked on the label. In terms of style and flavor, it may be worlds away from the last Grand Cru you drank. Check to see if there's a more accurate description of the beer style on the label, or even whip out your phone and do a little research before buying (yep, I'm that guy).Because you know what they say..a Grand Cru by any other brewery may not taste as sweet..or malty..or sour..well anyway, you get the idea.