As I get more and more familiar with the beverage, I begin to see how much there is to cider that we might not immediately perceive. Particularly here in the Northwest, where nearly every orchard apple was planted for eating, we tend to think of cider as a crisp, sweet drink characterized mainly by a light apple flavor. Because that's what eating apples produce. There's more to it than that.
In the old traditions, cider should actually be a more complex drink. The humble apple comes in a variety of types, and many of them are, as Abram Goldman-Armstrong calls them, "little gnarly, scabby things" no one would eat. But these apples are full of important compounds that give a proper cider its holy trinity of balance: tannins, acidity, and sweetness. Indeed, among these, perhaps the least important is sweetness. Sweet apples are loaded with sugar, but sugar is easily fermentable, so what you're left with is a neutral beverage. (Cider makers can "back-sweeten" a cider by adding apple juice back to the fermented cider to give it more flavor--and sweetness.)
|My July 4th cider: a Dupont.|
Acidity is more obvious--it's the same quality that sharpens the flavors of a Berliner weisse or gueuze. And while bitter apples have almost no eating appeal, some tart ones, like Granny Smith, do. The sharpness comes from malic acid--and the horticulturally inclined will recognize "malic" as the genus of apple trees (Malus). Acidity gives what oenophiles call "structure" to a cider--a refreshing crispness that enlivens the apple flavors.
Residual sweetness has its place in ciders--tannins and acids are strong players, and they need softening by a bit of the fruit's native sugars. Even dry ciders will have a bit of sweetness for balance.
One final note. Rarely will a single apple variety have a perfect balance of all three of these elements. Blending apple varieties is one of the great skills of cider-making. In this way, it's a lot like brewing a lambic. Blending isn't used to moderate or soften a beverage, as in whiskey, but to find richer balance points not available in single varietal or unblended stocks.